socio-spatial perspectives on the utilization of emergency hospital services in two urban...

Sec. Sri. MeMud. Vol. 30. No. I. pp. 53-66, 1990 Printed in Great Britain. All rights reserved

0277-9536890 53.00 + 0.00 CopyrIght C 1990 Pergamon Press plc

SOCIO-SPATIAL PERSPECTIVES ON THE UTILIZATION OF EMERGENCY HOSPITAL SERVICES IN TWO URBAN

TERRITORIES IN QUEBEC

FRAN~OIS BBLAND,' LISEPHILIBERT,'JEAN-PIERRETHOU& and BRIGI~ MAHEUX'

‘Groupe de recherche interdisciplinaire en santt and %epartment of Geography, Universitt de MontrCal, C.P. 6128, Succ. A, Montreal, Quebec, Canada H3C 357

Abstract-Hospital emergency services located in urban areas have been severely congested for several years in the province of Quebec. This problem is not caused by ambulatory patients who are using emergency services as a regular source of care, but by patients in need of emergency services. To study the factors affecting the utilization rates of emergency services in two urban areas, the city of Lava1 and the Quebec metropolitan area, two samples of more than 30,000 patients each were drawn from the 198 I file of the R&e de l’assurance-maladie du Quebec. The utilization rates of emergency services for emergent and urgent causes in these two samples were computed on the basis of the census tract location of these patients. The socio-economic characteristics of these census tracts were taken from the 1981 Canadian census, the distance travelled from each census tract to the location of hospital emergency services was computed and included as a predictor of the utilization rates. Also, the prevalence of chronic and psychiatric diagnoses were obtained for each census tract. The result of the analysis showed that distance at&ted the utilization rates only in the Quebec metropolitan area where the hospitals are mostly located in the downtown area near deprived and working class neighbourhoods, while the socio-economic characteristics affected the utilization rates in both Quebec and Laval.

Key worcis-hospitals, emergency services, factor analysis, Quebec

INTRODUCTION

The hospital emergency services in the province of Quebec have been experiencing problems of congestion for several years [l-3]. These problems are attributable to the length of stay at the emergency room of patients on stretchers who require medical, surgical or psychiatric attention and who frequently require hospitalization [4], rather than to patients who use the emergency room as a substitute for their regular source of care or as a usual source of care [S]. Studies on the utilization of emergency services have usually emphasized the reasons that cause an inappropriate use of this source of care [6-361. Since non-emergency ambulatory patients in Quebec do not cause the congestion of emergency services, it is important to study the utilization of emergency services for emergent and urgent problems.

The goal of this study is to examine the geographic, social and epidemiological conditions that are linked to the utilization of emergency hospital services for emergent and urgent causes. Several studies have shown that the type and frequency of utilization of emergency services vary according to the location of emergency services, the availability of other health care services and the patients’ characteristics [37-SO]. In the present study, the causes of the utilization of emergency services have been studied on two territories that have a radically different spatial distribution of hospital emergency resources. One of the territories is organized in a traditional way, in that underprivileged populations are located mainly at the centre of the city and have easy access to several emergency hospital care resources. On the other territory, the underprivileged populations are dis- persed and are not located in the neighbourhood of

emergency hospital services. The examination of the two territories allowed us to evaluate to what extent the variations in the utilization of emergency services for emergent and urgent causes depend on the geographic dispersion of emergency care resources, while controlling for the socio-demographic and epidemiological characteristics of the population.

The perspective of this study is ecological in the sense that the location of the patients on the two territories and the rates of use of emergency services are reported on the basis of census tracts [8]. This permits us to evaluate to what extent the variation in the rates of use among census tracts is attributable to location, socio-demographic characteristics or epidemiological variables in the population. This perspective allows us to understand the combined influences of the spatial distribution of the emergency resources and residential structure on the use of emergency services for emergent and urgent causes.

EMERGENCY CARE IN QUEBEC

In Quebec, the use of emergency services for emergent and urgent reasons comes from two sources: medical emergencies and social emergencies [S 11. Medically critical and urgent cases need more or less immediate (20 min to 12 hr) medical or surgical attention and may require hospitalization [52]. Diag- nostic and therapeutic equipment, staff and the hospital infrastructure of emergency rooms allow for rapid intervention, often a determining factor in the short term for the patients’ life or health [4]. About 50% of the critical and urgent medical cases are victims of trauma, bums and poisoning. The other half is composed of patients who undergo acute crises of chronic illnesses and serious episodes of acute ill-

53

54 FRANCOIS B~LAND et al

nesses [49]. These critical and urgent medical cases take up approx. 60% of the stretchers in an emergency department [4]. In 65% of the cases, they are hospitalized and account for at least a third of all the admissions to acute care hospitals [52]. On the average more patients are hospitalized for a longer stay than patients admitted for an elective procedure and they require a larger number of auxiliary services [53].

Although trauma, burns and poisoning are not forseeable events, certain groups of people are more at risk than others [54]. The victims of trauma are most often men, manual workers and young drivers of motorized vehicles [49]. Very young children, boys in particular, are more susceptible to being victims of bums and poisoning. Also, for certain subgroups of the population, health risks increase whereas the chances of recovery decrease [55]. Elderly people are more often affected by illnesses than trauma. They make up about 10% of the population of emergency room patients, which represents their proportion in the population of Quebec. More than a third of hospitalized elderly are admitted via the emergency room [56].

About 40% of the patients who occupy emergency room stretchers fall into the social emergency cate- gory. On the one hand, these patients’ length of stay in the emergency department is drawn out because of particularities inherent to the Quebec health care system [51]. For example, certain elderly people use hospital emergency rooms as a way into a long term care institution [4,47]. On the other hand, during the 197Os, hospital psychiatric care was reorganized on the basis of catchment areas. At the same time a great number of patients were deinstitutionalized [38]. The deinstitutionalized psychiatric clientele shows recur- rent use of emergency services in acute care hospitals [31, 57,58, 591, while community care are still un- available [60]. These are the people who have little or no social support, depend on governmental support and live in underprivileged environments [61,62].

In summary, the few studies available on the use of emergency services in Quebec indicate that geographic, socio-demographic and epidemiological variables may explain the type and frequency of use of this service. In this ecological study, we have evaluated, using data from two geographical areas, the influence of the distance from home to the emergency services, controlling for variables that have been shown to impact on use of health services. Though the effect of distance on the use of emergency services is well documented in the literature, the impact of the geographical distribution of hospital emergency rooms on this effect has not been exam- ined. In this study, two areas with divergent patterns of geographic availability of hospital emergency services is studied. This allowed for testing the effect of distance on emergency services used in two con- trasted situations. Differences in the effect of distance on the use of emergency services between areas with different patterns of location of hospital emergency services have not been documented in the literature.

DATA AND METHOD

The areas studied are the municipality of Lava1 and the Quebec metropolitan area (QMA). The city of

Lava1 is a multifunctional (residential, commercial and industrial) suburb of Montreal with a population of 268,295 in 1981 [63]. This island municipality has only one hospital on its territory, located in the centre of the island. Proximity to Montreal, however, offers a large choice of hospital resources (Fig. 1). The Universite de Montreal and McGill University house schools of medicine. A number of hospitals are affiliated with one or other of these schools. In contrast to the Quebec metropolitan area, a restricted number of hospital emergency rooms are available at a short distance from the Lava1 area. The QMA comprises 9 municipalities that had 424,145 residents in 1981. This metropolitan area is an urban agglom- eration structured like a North-American city: downtown, transition zone, urban fringe, suburbs and a semi-rural region. Several emergency hospital resources are easily accessible on the territory (Fig. 2). The Universitt Laval, located in the QMA, houses a school of medicine, while a number of hospitals are affiliated with this school. Ambulatory medical care is equally available at Lava1 and in the Quebec metropolitan area. Thus, except for the availability of hospital emergency rooms in their immediate vicinity, both areas are equally well equipped in medical and hospital resources.

The use of emergency services was estimated with the data on use of medical services in the province of Quebec available on the files of the Regie de l’assurance-maladie du Quebec (RAMQ). The RAMQ is the agency responsible for the payment of physician claims in the Quebec Health Insurance Plan. Two random samples were drawn from the 1981 users of health care services living in Lava1 and in the Quebec metropolitan area. The samples included 32,478 users in Lava1 and 32,392 users in the QMA. Each physician claim contains information on the user (an ID code, age, sex, postal code), on the physician (an ID code, specialty) and on the medical procedures (the specific medical procedure, the facility where it was performed, whether the procedure was performed in an out-patient or in-patient context and the diagnoses as coded by the RAMQ).

To exclude cases temporarily residing outside Lava1 or the Quebec metropolitan area, we kept only the data on medical procedures performed in hospital emergency departments located within a radius of 30 km from our two regions. The final sample for Lava1 was 31,816 users spread over 53 census tracts for whom 250,977 medical procedures were performed in 1981. The final sample from the Quebec metropolitan area was 32,046 users spread over 97 census tracts for whom 279,706 medical procedures were performed for the same year.

Dependent variable

The utilization of emergency services for emergent and urgent causes implied that the patient should show a serious medical, surgical, or psychiatric condition requiring rapid intervention. The codification system of the RAMQ for medical care delivered in hospital identified whether a procedure was performed on an ambulatory patient, in an out-patient or an emergency hospital department, or on an in-patient. We used four criteria to determine whether or not the ambulatory medical services delivered in a

IOEN

TIFI

CA

TIO

N

l- SR

lNlE

J&

TINE

2-

6E

NERx

JJ

IF

3-

ST-N

mY

4-

COTE

OES

EEI

GES

5-

G

ENER

X n

)UW

TF!E

RL

6-

ROYf

iL V

ICTO

RIA

7-

HONl

fW_

FUUf

l EW

ANTS

8-

9R

INT

- LK

9-

W

NTE-

.EfM

E O

’fNK

IO-

HOTE

L DI

N O

E m

Nlfw

lL

IL-

NolR

E -

ImE

LZ-

)(AIs

aEaM

-Ro6

ffmNT

IJ

- M

WE

- DC

IWT

14-

INST

ITUT

tE

Cf

HllM

MlE

1%

6R

NTfi

CFBf

iINI

16-

6filN

T -

tllCH

EL

I?-

JERW

- TF

UlW

16

- FL

EURY

liR

lam

OI

8 G

em.

lADE

Rl w

LI

ES F

llILl

ml

LS-

9KRE

-

cmrl

6.R

l.S.

“a

I 20

- SA

INT

- LR

JREN

T JM

Is

m

Zl-

CITE

CE

LA

WlE

DE

LRI

lR

22-

ST-E

USTR

M

Fig.

I.

Hos

pita

l lo

catio

ns,

Lav

a1 (

1981

).

_ ^

.- .

~ -

- .

. . i

= _

_ .

_~ -

_. _

. _

_ _

_ _

. . Y

^

_

-.

_

>~

.

. -

~_

__

.__

_

_

_._

__

-__

v-

m_.

. .--

L--r

-

56 FRANCOIS B~LAND et al.

Emergency hospital services in Quebec 57

hospital had been for emergent and urgent causes. The first criterion was the diagnosis recorded on the physician claims; the second was the combination of the diagnosis and the medical procedure performed; and the third and fourth criteria considered the type of medical care received either before or after the use of an ambulatory care service in a hospital. The dependent variable in this study is therefore an approximate measure of the use of emergency services for emergent and urgent causes. Thus, care should be used in the interpretation of the results of the analysis.

numbe; of these diagnoses made it difficult for the physicians to draw a conclusion as to the necessity of

Diagnosis and medical procedure served as indica- tors of the seriousness of the case. Some diagnoses described physical or psychological states that needed an immediate intervention and some medical procedures were performed exclusively in an emergency context. The diagnosis and procedures were classified according to their emergency status by physicians. An initial list of 500 diagnoses drawn from ICD-9 (1975 version) was first submitted to 3 ohvsicians. A certain

Table 2. Independent variables: averages by region

Lava1 Quebec

Weighted average distance travelled % Men % Individuals under 4 yr old % Individuals from 65 to 69 yr old

% Individuals with education only

primary school 18.90 23.84

% Working in services 20.04 31.00 % Manual workers 50.02 36.09 % In primary industry 1.72 1.83

% Employment revenue 93.30 92.64 % Transfer revenue 12.24 25.11 % Investment revenue 12.09 13.39

Rate of unemployment % Widowed individuals % Separated or divorced individuals % Single parent families

10.67 4.42 3.53

10.69

12.39 6.48 4.43

16.53

% Rented housing

% Individuals with psychiatric problems

34.21

9.25

58.31 % Gross rent 6300 and under

10.62

67.51

% Individuals with chronic illnesses

76.50 % Housing with major repairs

42.01

5.42

46.24

7.10 Average number of individual/room 0.55 0.54

8.25 km 8.11 km 49.20 47.01

6.30 5.08 2.50 4.44

prompt intervention without additional information. For each of these diagnoses we prepared a list of the medical procedures with which they were associated according to our samples. This list of diagnosis and procedure combinations was submitted to 4 other physicians in order to obtain criteria for the classifi- cation of out-patient services use for emergent and urgent causes or for other causes.

The temporal sequences of the utilization of health care services allowed us to elaborate two other criteria on the utilization of emergency services for emergent and urgent causes. If a beneficiary was hospitalized for less than 24 hr after a visit to an out-patient facility according to the RAMQ files, we concluded that the patient used the emergency room rather than the out-patient clinic. As well, when a patient received an urgent medical visit at home and used an out-patient facility less than 24 hr later, we concluded that he or she had used the emergency department.

We applied all these criteria in order to select the patients who made use of emergency services for emergent and urgent causes. Since a beneficiary could be selected by means of several criteria, the numbers obtained could not be added. We combined all the files, then eliminated the repetitions to obtain the number of users of emergency services for emergent and urgent causes per census tract (Table 1).

The 5402 users of emergency services for emergent and urgent causes from Lava1 and the 8706 users of

these services in the QMA allowed us to calculate a utilization rate of emergency services for emergent and urgent causes per census tract. The dependent variable in this study was the ratio of the number of users of the emergency services for emergent and urgent causes to the users of ambulatory medical care services. Both the numerators and the denominators were obtained from the RAMQ data file. The number of users of ambulatory medical care was used as the denominator instead of the population living in the census tract because we were not studying access of a population to health care in general. The issue here concerns a population of users of medical services, some of whom use medical care for emergent or urgent reasons in hospital emergency services, while others use other sources of ambulatory medical care services. In the province of Quebec, on a yearly basis, 80% of the population use an insured medical care service.

Independent variables

The explanatory variables were aggregated at the level of the census tract. Two epidemiological variables were developed from the RAMQ files. The ratio of the number of people who received a diagnosis related to somatic chronic illnesses or psychiatric illnesses was computed. The 16 socio-demographic and socio-economic variables came from the 1981 Canadian census (Table 2). These variables were chosen to measure exposure to the risk of using

Table 1. Reference population: sample selection criteria

Selection criteria Lava1 Quebec

Number of census tracts 53 97 1981 population Sample of RAMQ users

emergency services for-emergent and urgent cond: tions, such as percentages of very young children, elderly people, men, manual workers, percentage of

268,295 424,145 individuals with low education, single parent families 31,876 32,046 and oercentaee of income from social welfare

Emergency-diagn&s 4,186 6.630 Emergency treatmentdiagnoses 1,768 2,960 Hospitalization via emergency department 1,181 1,875 Emergency home visit 174 448 Emergency department users for emergent 5,402 8,706

programme. _ Socio-economic and socio-demographic variables

measured on the basis of census tracts are usually highly correlated. The correlation matrix of the 16

and urgent causes Rate for the region in the sample 16.95% 27.17%

v&ables from the QMA had a condition number of 170.7. The corresponding figure is 143.1 for the

58 FRANCOIS B~LAND et ul.

Table 3. Orthogonal factor analysis

Variables Factor I Factor 2 Factor 3

A. METROPOLITAN AREA OF QUEBEC CITY Divorced Sinale-aarent family Relted housing ’ Rent $300.00 and less Widowed Men Investment income Elderly people Young Primary school Manual workers Services Housing needing repairs Social security

Divorced Single-parent family Rented housing Rent $300.00 and less Widowed Men Investment income Elderly people Young Primarv school Manual workers Services Housing needing repairs Social secunty

0.875 0.000 0.000 0.554 0.353 0.000 0.754 0.408 0.000 0.313 0.000 0.787 0.000 0.798 0.000 0.000 -0.654 0.000 0.319 0.582 0.000 0.000 0.480 0.000

-0.502 -0.603 0.000 0.453 0.000 0.820 0.000 0.000 0.824 0.563 O.OCG 0.451 0.380 0.396 0.374 0.707 0.326 0.435

B. LAVAL

0.859 0.869 0.880 0.3% 0.000 O.OOil 0.000 0.000 0.000 0.000 0.000 0.000 0.000

0.000 0.000 0.308 0.000 0.861

-0.343 0.417 0.861

-0.615 0.000

-0.461 0.000 0.000

O.OOG 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.912 0.604 0.624 0.446

0.253 0.426 0.594

correlation matrix from the Lava1 data set. Problems of collinearity appear with a condition number equal to or higher than 30 [64]. Thus, an orthogonal factorial analysis was performed on each of the set of data.

The loadings of two variables were low on each of the factors. These were the proportion of unemployed and the proportion of total income from employment. The correlations of these two variables with the others in the data set were low compared with the correlations between these other variables among themselves.

The numerator of D,> is the sum of the number of kilometres travelled by the users of emergency rooms in census tract i to all of the hospitalsj. This number is divided by the total number of users of emergency services. Because more than one hospital emergency service was used in any census tract, we computed a global index of distance that weight the importance of utilization of each emergency room in each census tract.

The results of the factor analyses are found in Table 3. Three factors accounted for 68.4% of the variance in the QMA and 59.0% in Laval. The solution for the Lava1 data set was more easily interpreted than the solution for the QMA data set, though both have some common features. Using the Lava1 data set, the first factor identified the single- parent families. The second dimension was clearly linked with characteristics of an ageing population, while the third factor was indicative of lower class neighbourhood. Finally, income from social security programmes loaded on the three dimensions.

The three dimensions were more or less identified in the QMA data set, the loadings overlapped on many factors. Nevertheless, the main features of the factors in this analysis were located along the dimensions found in the results from the Lava1 data set.

Two regression equations were estimated, one using the data from Lava], the other the data from the QMA. In each case, the univariate effect of distance on the utilization rates of emergency services for emergent and urgent causes was estimated. The non- standardized regression coefficients obtained in Lava1 and in the QMA were compared to show how two different spatial distributions of emergency services affect the relation between distance and use of emergency services for emergent and urgent reasons in areas equally well equipped in ambulatory medical care and hospital beds. But the effect of distance can be accounted for by other factors. The second step of the regression analysis allowed for the control of the effect of distance on use of emergency services for emergent and urgent reasons for socio-demographic, socio-economic and health risk factors. The condi- tional estimates of the effect of distance in the two areas were again compared.

RESULTS

The three dimensions relate to exposure to risk The utilization rates of emergency services for factors for the use of emergency services. The propor- emergent and urgent causes were higher in the QMA tion of unemployed and the proportion of income than in Laval. The average of the utilization rates was from employment were added as these two variables 27.2% in the QMA versus 17.0% in Laval. Indeed, were not loading on the factors identified in Table 3. the maximum rate of use of emergency services for Though correlated with these factors, the values of emergent and urgent reasons observed in the Lava1 the correlations were in the low to moderate range census tracts did not even attain the average of the (-0.284 to 0.275 for the QMA and -0.253 to 0.174 rates of the Quebec metropolitan area. As a matter of

for Laval). At these levels, no collinearity problems occurred. Finally, the proportion of individuals with chronic illnesses and the proportion with psychiatric diagnosis were included in the set of independent variables.

The origin-destination distances were measured from centroids of the census tracts of residence to centroids of the census tracts for the location of hospital centres. Thus, the distances were not measured along roads. The measure of distance obtained was an approximation to the real distances. This procedure is acceptable when the areas are small, as is the case with the census tracts used here [65]. We constructed two matrices of the distances in kilometres, one for Lava1 and the other for the Quebec metropolitan area. From these data, we computed the weighted average distance travelled per census tract. This measure was obtained by multiplying the distance D,, from the census tract i to the tractj where the hospital is located by the number of users of hospital emergency room N,. These results were added for each of the hospital emergency rooms j. The distances weighted in this way were divided by the number of users N, from the census tracts i, as in:

60 FRASCOIS BI~LAND er al

1 I I I


fact, 73 census tracts of the QMA had a utilization

Table 4. Univariate and multiple regressions: Lava1

Distance R=

Distance Single-parent family Ageing Low SSE % Unemployed % Income from work % Chronic illnesses % Psychiatric diagnosis

R’ (adjusted)

Standardized Regression Standard regression coefficient tTm0l- P-lCV.4 coefficient

A. IJNIVARIATE REGRESSION -0.02 0.1 I 0.85 -0.026

0.00

8. MULTIPLE REGRESSION - - NS - - - NS - - - NS - 1.47 0.30 0.00 0.54 0.25 0.11 0.03 0.25 - - NS - - - NS - - - NS -

0.382

rate above the highest rate (24.4) observed in Laval, whereas the 24 other tracts had a utilization rate below 24.4. As shown in panel A, Table 5, the variation in the utilization rates in Quebec was directly related to the distance from the census tract to the location of emergency hospital services (Figs 3 and 4). The 24 census tracts that had a rate of use below 24.4 were located on the average of 11.9 km from emergency hospital services; the 74 census tracts that had a utilization rate above 24.4 were located on the average at 6.9 km from emergency hospital services.

Distance did not influence the use of emergency services for emergent and urgent causes in Lava1 (Table 4). Figure 5 shows that Lava1 users who were the farthest from the Montreal hospitals travelled the longest distances in order to use emergency resources. Figure 6 shows that utilization rates varied only very little in relation to distance except for the census tract where the area’s hospital centre was located. The people who resided in this tract frequently used emergency services.

The non-standardized regression coefficients for distance in the two data sets (Tables 4 and 5) were clearly different. Panel B of Table 5 shows that the introduction of socio-economic, socio-demographic and epidemiologic factors lowered the estimation of the effect of distance in the QMA. Nevertheless, this effect remained highly significant. Thus, controlling for other variables did not modify the conclusion that

distance has a different impact on use of emergency services for emergent and urgent conditions in Lava1 and in the QMA.

In Lava], only two independent predictors were significant in the regression model, that is, low social class neighbourhood and proportion of unemployed (Table 4). The variance explained by these two variables reached 38.2%.

Both in Lava1 and in the QMA, the epidemiological variables were highly correlated with the ‘single- parent family’ factor (0.406 < r < 0.592). The proportion of individuals with chronic diseases was also highly correlated (0.524 < r Q 0.600) with the ‘ageing population’ factor. These associations were as expected inasmuch as environments with a high proportion of single-parent families are usually deprived neighbourhoods with a high risk for psychiatric and other chronic diseases. Also, an ageing population is prone to chronic illnesses. These high correlations between the epidemiological variables and two of the socio-economic and socio-demographic factors could have produced problems of collinearity. This was not the case in Lava1 inasmuch as the correlations of the epidemiological variables with emergency services use were low and not statis- tically significant. In the QMA, both epidemiological variables were highly correlated with the dependent variable in this study. Thus, problems of collinearity were a possibility. As a matter of fact, the effect of ‘single-parent family’ on the risk of use of hospital emergency services for emergent and urgent condi-

Table 5. Univariate and multiole regressions: Ouebec citv metrooolitan area

Distance R’

Regression Standard coefficient CmOr P-level

A. UNIVARIATE REGRESSION -0.64 0.09 0.00

B. MULTIPLE REGRESSION Distance -0.41 0.11 0.00 Single-parent family -1.12 0.52 0.03 Ageing - - NS Low SSE - - NS % Unemployed - - NS % Income from work - NS % Chronic illnesses ;50 0.13 0.00 % Psychiatric diagnosis 0.20 0.07 0.01

Standardized renression coefficient

-0.59 0.339

-0.38 -0.22

- - - - 0.36 0.29

R’ (adjusted) 0.593

FRASCOIS B~LANLI et al.

64 FRANCOIS B~LAND er al

tions was negative. This estimate can be interpreted either as the effect of collinearity or as the effect of ‘single-parent family’ on the risk of emergency care use for emergent and urgent conditions when the risk for psychiatric illnesses was accounted for. Within the context of this study, it is difficult to choose either interpretation, but the second hypothesis makes sense inasmuch as a high proportion of single-parent families in a census tract is an indicator of a concen- tration of psychosocial problems conducive to mental health problems. Thus, psychiatric illnesses are prob- ably one of the causes for emergency services use in census tracts with many single-parent families.

In summary, in the context of geographical accessibility to several hospital emergency resources located mainly in the central districts, such as in the QMA, proximity constituted a determining factor in the risk to use hospital emergency services for emergent and urgent conditions. But, in the context of geographical accessibility to a restricted number of hospital emergency resources not easily accessible by public transportation, such as in Laval, distance from the hospital emergency services was not a determinant factor in the risk to use hospital emergency services for emergent and urgent conditions.

DISCUSSION

The results of the analyses suggest that the effect of geographical distance on the use of emergency services from emergent and urgent causes may depend on the geographical distribution of hospital emergency resources. Indeed, in this study, the use of emergency services for emergent and urgent causes was influenced by distance only in the QMA. In Laval, this influence is nil.

The relation between the use of emergency services for emergent and urgent conditions and distance was diminished, but remained significant in the QMA, when the socio-economic and epidemiological conditions were entered in the regression equation. There- fore, distance has an effect on the use of emergency services for emergent and urgent causes in the QMA even though factors such as family life, and the rates of chronic and psychiatric illnesses were controlled.

The relationship of distance to use could have been explained by factors that were not introduced in this study for lack of availability. The first concerns the availability of medical resources other than hospital emergency rooms in certain medical emergency cases in census tracts that are relatively far away from hospital emergency services. The second concerns cultural factors that affect, on the one hand, relations between the physician and the patient and, on the other hand, relations between the lay referral system (relatives, friends, etc.) of users and the professional referral system (medical and paramedical) [66].

The explanation of the effect of distance on the use of emergency services for emergent and urgent causes could come from the availability and use of emergency medical resources outside hospitals for people who are far away from hospitals. These resources could be used by these people for minor emergencies, i.e. for conditions that, while needing quick intervention, require simple medical equipment and non-specialized medical staff. These resources are equally

available in the QMA and in Laval. The use of such a type of resource could be characteristic of the middle classes rather than of the underprivileged classes, which would explain the more frequent use of hospital emergency services by the latter in Laval. In the QMA on the other hand, the availability of hospitals to underprivileged census tracts may pro- mote the use of the emergency department of the hospital for any emergent or urgent condition, whether it needs specialized medical equipment and staff or not. Here, there would therefore be a correlation between the effect of the location of emergency resources, populations at risk and cultural factors that affect the way medical services arc used. These correlations cannot be estimated with the data available here.

Finally, we suggest that the patterns of association, between use and distance, on the one hand, and distance and socio-economic and epidemiological factors, on the other hand, appeared in this study because of the difference in the geographical accessibility of hospital emergency services in the two areas. We can thus formulate the hypotheses that (a) the relationship of distance to the social and epidemiological factors depends on the interaction between the location of hospitals and the territorial dispersion of specific social groups, while (b) the relationship of social and epidemiological factors and use depends on the capacity of social groups to mobilize the resources needed to use the services. These relation- ships should be systematically studied in further research to identify the process by which distance affects use of hospital emergency services for emergent and urgent conditions. As suggested by our results, the geographical distribution of the hospital emergency services should be systematically controlled for in further studies. It should not be taken for granted that distance affects the use of emergency services in every case. Bohland [8] has made the point that factors that impact on the use of emergency services in a metropolitan area vary from those that explain the use of a hospital emergency service located in a specific catchment area. A catchment area of a hospital within a city differs in many ways from other hospital catchment areas located in that same city.

REFERENCES

1. Dutil R. La problematique des salles d’urgence de Montreal. L’OMNI 8, l-3, 1985.

2. Drapeau G. et al. La problematique des salles d’urgence region 06-A. 1’Association des omnipraticiens de Mon- treal. Montreal, May 1985.

3. Minis&e des Affaires sociales et conseil regional de la Sante et des Services sociaux de Quebec. Analyse de la probltmatique de l’engorgement dans les services d’urgence du Quebec mttropolitain. Quebec, Summer 1983.

4. Spitzer W. Analyse statistique, operationnelle et clinique du phenomene de l’engorgement des salles d’urgence des centres hospitaliers de courte duree de la region montrealaise. Research report, McGill Univer- sity, Montreal, 1985.

5. Torrens P. R. and Yedvab D. G. Variation among emergency room populations: a comparison of four hospitals in New York City. Med. Cure 8, 6&75, 1970.

6. Andren K. G. and Rosenqvist U. Heavy users of an


emergency department: a two-year follow-up. Sot. Sci. Med. 25, 825-831, 1985.

7. Bain S. and Johnson S. Use and abuse of hospital emergency departments. Con. Fans. Physicn 17, 33-36, 1971.

9.

10.

11.

12.

13.

14.

15.

16.

17.

8. Bohland J. Neighborhood variations in the use of hospital emergency rooms for primary care. Sot. Sci. Med. 19, 1217-1226, 1984. Boileau L. er al. Rapport d’etude descriptive sur l’utilisation de l’urgence de Maisonneuve-Rosemont par la clientele ambulante. DCpartement de Sante communautaire, Centre hospitalier Maisonneuve-Rosemont, Montreal. April 1983. Calnan M. The hospital accident and emergency department: what is its role? J. Sot. Policy 11, 483-503, 1982. Chaiton A. Trends in emergency department utilization. Can. Funs. Physicn 21, 115-122, 1975. Davies T. Accident department or general practice. Er. Med. J. 292, 241-243, 1986. Davison A. G., Hildrey A. C. C. and Flayer M. A. Use and misuse of an accident and emergency department in the east end of London. J. R. Sot. Med. 76,37-40,1983. Departements de Sante communautaire Enfant-Jesus, St-Sacrement, CHUL. Les services medicaux d’urgence dans la Quebec-metro: la dynamique de l’offre et de la demande. Quebec, May 1985. Elliot M. and Vayda E. Characteristics of emergency department users. Can. J. publ. Hlth 69, 233-238, 1978. Geyman J. P. Trends and concerns in emergency room utilization. J. Fam. Pruct. 11, 23-24, 1980. Gibson G. and Mackenzie E. J. Patterns of trends of utilization of emergency medical services. In Principles and Practice of Emergency Medicine (Edited by Schwartz G. R. er al.). Saunders, Philadelphia, Penn., 1986. Gifford M. J., Franaszek J. B. and Gibson G. Emer- gency physicians’ and patients’ assessments: urgency of need for medical care. Ann. Emerg. Med. 9, 502-507. 1980. Hansagi H. er al. Trial of a method of reducing inappropriate demands on a hospital emergency department. Publ. Hlrh 101, 99-105. 1987. Hilditch J. R. et al. Judging the appropriateness of patients’ visits to the emergency department. Gun. Fum. Phys. 28, 686688, 1982. Jacoby L. E. and Jones S. L. Factors associated with emergency use by ‘repeater’ and ‘nonrepeater’ patients. J. Emera. Nurs. 8. 243-247. 1982. KleimanM. B. Who uses the hospital emergency room: correcting a misconception. Hosp. Hlth Serv. Admin. 26, 63-71, 1981.

18.

19.

20.

21.

22.

24.

25.

23. Langlois D. er al. Etude sur l’utilisation des services d’ureence de l’houital Charles Lemovne. Raunort me- limiiaire. DSC Charles Lemoyne, Montreal; August 1986. Lavenhar M. A., Ratner R. S. and Weinerman R. E. Social class and medical care: indices of non urgency in use of hospital emergency services. Med. Cure 6, 368-380, 1968. Lees R. E. M., Steele R. and Spasoff R. A. Primary care for non traumatic illness at the emergency department and the family physician’s office. Can. Med. Ass. J. 114, 333-337, 1976. Magnusson G. The hospital emergency department as the primary source of medical care. Scund. J. Sot. Med. 8, 149-156, 1980. Myers P. Management of minor medical problems and trauma: general practice or hospital? J. R. Sot. Med. 75, 879-883, 1982. Parboosingh J. E. and Larsen D. E. Factors influencing frequency and appropriateness of utiliaation of the emergency room by the elderly. Med. Cure 25, 1139-l 147, 1987.

26.

27.

28.

29.

30.

31.

32.

33.

34.

35.

36.

Powers M. J.. Reichelt P. A. and Jalowiec A. Use of the emergency department by patients with non-urgent conditions. J. Emerg. Nurs. 9, 145-149. 1983. Purdie F. R. J., Honigham B. and Rosen P. The chronic emergency department patient. Ann. Emerg. Med. 10, 298-301, 1981. Schneider K. C. and Dove H. G. High users of VA emergency room facilities: are outpatients abusing the system or is the system abusing them? Inquiry 20,57-64, 1983. Siemiatycki J. and Richarson L. Statut socio- Cconomique et utilisation des services de same a Mon- treal. L’actualite economique 2, 194-210, 1980. Steinmetz N. and Hoey J. R. Hospital Emergency room utilization in Montreal before and after Medicare: the Quebec experience. Med. Cure 16, 133-139, 1978. Wabschall J. M. Why parents use the emergency department for non emergency infant care. J. Emerg. Nurs. 9, 37-40, 1983. Wan T. T. H. and Broida J. H. Factors affecting variations in health services utilization in Quebec, Canada. Socioecon. Plunn. Sci. 15, 231-242, 1981. Weinerman E. R. er al. Yale studies in ambulatory medical care: determinants of use of hospital emergency services. Am. J. publ. Hlth 56, 1037-1056, 1966. - . _.

37. Cualiani A. Patterns of hosoital based ambulatorv care.

38.

39.

40.

41.

42.

43.

44.

45.

46.

47.

48.

49.

Soi Sci. Med. 12C, 55-58: 1978. *

Foggin P. M. La localisation des services d’urgence psychiatrique sur Tile de Montreal. Sante ment. Quebec 7, 7487, 1982. Ingram D. R., Clarke D. R. and Murdie R. A. Distance and the decision to visit an emergency department. Sot. Sci. Med. 12, 55-62, 1978. Jones P. K., Jones S. L. and Yoder L. Hospital location as a determinant of emergency room utilization patterns. Pub/. Hhh Rep. 97, 445-451, 1982. Magnusson G. The role of proximity in the use of hospital emergency departments. Social. Hlth Illness 2, 202-214, 1980. O’Grady K. F. et 01. The impact of cost sharing on emergency department use. New Engl. J. Med. 22, 848-853, 1985. Perkoff G. T. and Anderson M. Relationship between demographic characteristics, patient’s chief complaint and medical care destination in an emergency room. Med. Care 8, 309-323, 1970. Roghmann K. and Zastowny T. Proximity as a factor in the selection of health care providers: emergency room visits compared to obstetric admissions and abor- tions. Sot. Sci. Med. 13D. 61-69. 1979. Scherzer H. N., Druckman R. and Alpert J. J. Care- seeking patterns of families using a municipal hospital emergency room. Med. Care 18, 289-296, 1980. Shannon G. W. and Dever A. G. E. Health Care Delivery, Spatial Perspectives. McGraw-Hill, New York, 1974. Ullman R., Block J. A. and Stratman W. C. An emergency room’s patients: their characteristics and utilization of hospital services. Med. Cure 13, 101 l-1020, 1975. Vaslamatxis G. R. et al. Social and resource factors related to the utilization of emergency psychiatric services in the Athens area. Acrapsychiar. stand, 75,95-98, 1987. Vayda E., Gent M. and Hendershot A. Emergency department use at two Hamilton hospitals. Gun. Med. Ass. J. 112, 961-965, 1975.

50. White H. A. and O’Connor P. A. Use of the emergency room in a community hospital. Publ. Hlrh Rep. 85, 163-168, 1970.

51. Bureau de Coordination des Centres hospitaliers d’enseignement affiliis a l’universite de Montreal. Ac- cessibilitt aux services en milieu hospitalier, Reflexion

66 FRANCOIS B~LAND er al.

collective des directeurs des services professionnels et recommendations au comite de recteur. Montreal, De- cember 1982.

52. Lebel L. et al. Etude descriptive de la clientele de l’urgence 11 Rvrier au 9 mars 1980, Departement de Sante communautaire de I’hopital Sac&Coeur, Mon- treal, 1980.

53. Kessler M. S. and Wilson K. C. Emeraencv deuartment key factor in hospital admissions. Ho~pirals Si, 87-92, 1978.

54 Haddon W. Jr and Baker S. P. Injury control. In Preventice and Community Medicine (Edited by Clark D. and MacMahon B.). Little, Brown, New York, 1981.

55.

56.

57.

Mackenzie E. J. and Waller J. A. Epidemiologic factors in emergency care. In Principles and Practice of Emergency Medicine (Edited by Schwartz G. R. et al.). Saunders, Philadelphia, Penn., 1986. Gupta R. C., Setty R. S. S. and Joshi D. M. Pensioners attending an accident and emergency department. Age & Ageing 1, 21-29, 1985. Lebeau A. La rtutilisation des services d’urgence pour des problimes de Sante mentale dans -la region metropohtaine de Montreal. Sante menr. Quebec 7, 57-74, 1982.

58. Lebeau A. Les grands utilisateurs des services

psychiatriques d’urgence. Carrefour aks aflaires sociales 7, 8-10. 1985.

59. Robertson B. M., Campbell W. and Crawford E. Risk versus motivation: the emergency room treatment of attempted suicide. Can. J. Psychiat. 32, 136-142, 1987.

60. Soskis C. W. Emergency room on weekends: the only game in town. Hlrh Sot. Work 5, 37-43, 1980.

61. Andren K. G. and Rosenqvist U. Heavy users of an emergency department: psychosocial and medical characteristics, other health care contacts and the effect of a hospital social worker intervention. Sot. Sci. Med. 21, 761-770, 1985.

62. Olsson M., Edhag 0. and Rosenquist U. Emergency care. Identification of psychosocial problem. &and. J. Sot. Med. 14, 87-91. 1986.

63. Statistique Canada. Canadian Census 1981. File EACII-A10 to EAY81-BlO(15) CANSIM Division, Ottawa, 198 I.

64. Belsley D. A., Kuh E. and Welsch R. E. Regression Diagnostics: Identifying Influential Data and Sources of Collinearity. Wiley, New York. 1980.

65. Bay K. S. and -Nestman L.’ J. A hospital service populations model and its applications. Int. J. HIth Serv. 10, 667-695, 1980.

66. Friedson E. Profession of Medicine, Harper & Row, New York, 1970.

socio-spatial perspectives on the utilization of emergency hospital services in two urban...

Documents