JOURNAL OF WOMEN'S HEALTHVolume 5, Number 4, 1996Mary Ann Lieber!, Inc.

Patient and Physician Gender May Influence ColorectalCancer Screening by Resident Physicians

MARIE L. BORUM, M.D., M.P.H.

ABSTRACT

Colorectal cancer causes significant morbidity and mortality in the United States. Despite thepublication and acceptance of screening guidelines, there is evidence that physicians incon-sistently adhere to the recommendations. Recent data also suggest that women may therebyreceive inadequate cancer surveillance. This study was designed to evaluate internal medi-cine residents' performance of colorectal cancer screening at The George WashingtonUniversity Medical Center during 1989-1994. A retrospective chart review of 200 medicalrecords (110 women, 90 men) revealed that resident physicians performed 85 (42.5%) rectalexaminations, 95 (47.5%) fecal occult blood tests, and 21 (10.5%) flexible sigmoidoscopies.Among the 110 female patients, 41 (37.3%) had rectal examinations, 43 (39.1%) had fecal oc-cult blood testing, and 13 (11.8%) had flexible sigmoidoscopies. Among the 90 male patients,44 (48.9%) had rectal examinations, 52 (57.8%) had fecal occult blood testing, and 8 (8.9%) hadflexible sigmoidoscopies. Male patients had significantly more (p < 0.008) fecal occult bloodtests than female patients. In addition, female physicians performed more rectal examinations(p < 0.04) and fecal occult blood testing (p < 0.02) on their female patients than did male physi-cians. Male physicians performed more rectal examinations (p < 0.04) on their male patientsthan did female physicians. Efforts should be made to improve screening practices by resi-dent physicians. Additional research should be conducted to evaluate the impact of patientand physician gender on the implementation of colorectal cancer screening guidelines.

INTRODUCTION malignant lesions have the potential to im-prove survival.2 Therefore, several organiza-

COLORECTAL cancer causes significant mor- tions have published recommendations forbidity and mortality in the United States, colorectal cancer surveillance. The primary

It is estimated that in 1996, there will be ap- methods of surveillance include annual rectalproximately 150,000 newly diagnosed cases examinations, annual testing of stool for occultand 60,000 deaths resulting from this malig- blood, and flexible sigmoidoscopies every 3 to

nancy.1 It has been noted that early detection 5 years.3,4and treatment of premalignant and localized Despite the publication and acceptance of

Division of Gastroenterology and Nutrition, The George Washington University Medical Center, Washington, DC.

363

364 BORUM

recommended surveillance procedures, there isevidence that physicians inconsistently adhereto cancer screening guidelines.5-10 Recent dataalso suggest that women may receive inade-quate cancer surveillance.11 Research has sug-gested that factors significantly influencingphysician compliance include physicianknowledge of screening guidelines and accep-tance of recommendations.810"15 It has, there-fore, been suggested that education and rein-forcement of screening practices duringresidency can influence subsequent practicepatterns.Published data addressing resident physi-

cians' performance of colorectal cancer screen-ing are limited. In addition, no previous studyhas assessed whether gender influences screen-ing practices. This study was designed to eval-uate resident physicians' performance of co-lorectal cancer screening in the ambulatory careclinic at The George Washington UniversityMedical Center, Washington, DC, during1989-1994. The impact of patient gender on res-idents' adherence to published guidelines was

explored.

MATERIALS AND METHODS

The George Washington University MedicalCenter has an accredited internal medicine res-

idency. There are approximately 20 to 25 resi-dent physicians in each of the 3 years of resi-dency. The resident physicians participate in a

weekly ambulatory care clinic during their sec-ond and third years of postgraduate training.Provision of longitudinal care by the residentphysician is directly supervised by one attend-ing physician during the 2 years. The recom-mended colorectal cancer screening proceduresfor patients include annual rectal examinations,annual testing of stool for occult blood, andflexible sigmoidoscopies every 3 to 5 years inpatients >50 years of age. These guidelineswere accepted by the division of general inter-nal medicine. The resident physicians receivedverbal and written information about these ac-

cepted surveillance techniques.The patients in this investigation received

their health care in the resident physician am-

bulatory care clinic. Patients who chose to re-ceive their health care from physicians in thedivision of general internal medicine at TheGeorge Washington UniversityMedical Centerwere assigned to the resident physicians' clinicbased on their desired appointment time. Thepatients were arbitrarily assigned to specificresident physicians. Each resident physiciancared for two or three individuals in this pa-tient population. The resident physician patientpopulation was similar to the patient popula-tion cared for by the attending physicians inthe division of general internal medicine. Therewas no apparent difference in the rate of hos-pital referrals, insurance status, or comorbidi-ties between patient populations seen by theresident physicians and by the attending physi-cians.This study was a retrospective chart review

of resident physicians' colorectal cancer screen-ing during 1989-1994. The study design wasreviewed by the institutional review boardof the George Washington University MedicalCenter. The medical records included in thestudy were of patients who were >50 years andwho had received longitudinal health care, in-cluding a health maintenance evaluation, by aresident physician. Medical records were ex-cluded if the patient had a history of malig-nancy, an increased risk for colorectal cancer,gastrointestinal complaints, was evaluatedonly for a specific problem, or had received di-rect health care by an attending physician.All medical records of resident physicians

that met the inclusion and exclusion criteria be-tween 1989 and 1994 were available for review.The performance of colorectal cancer screeningwas assessed. Screening methods were consid-ered to be performed if there was documenta-tion in the chart. The Epi Info program (version6, CDC, Atlanta, GA) was used to develop adatabase and for analysis. Statistical signifi-cance was determined by using contingency ta-bles, which generated Chi-square and p val-ues.16 Statistical significance was confirmedusing the InStat program (GraphPad Software,Inc., San Diego, CA), which employed Fisher'sexact test and two-tailed analysis to generate pvalues.17,18

GENDER MAY INFLUENCE COLON CANCER SCREENING 365

Table 1. Patient Characteristics

Total Males Females(n=200) (n=90) (n = 110)

Age (years)MeanMedianRange

RaceAfricanAmerican

WhiteHispanicAsianUndocumented

Insurance statusCommercialMedicare/Medicaid

Commercial/Medicare

Uninsured/self-pay

Undocumented

64.464.050-89

63.862.550-89

64.965.050-85

127 (63.5%) 53 (58.9%) 74 (67.3%)

56 (28.0%)5 (2.5%)2 (1.0%)10 (5.0%)

74 (37.0%)66 (33.0%)

19 (9.5%)

30 (15.0%)

11 (5.5%)

28 (31.1%)1 (1.1%)2 (2.2%)6 (6.7%)

33 (36.7%)30 (33.3%)

7 (7.8%)

17 (18.9%)

3 (3.3%)

28 (25.5%)4 (3.6%)0 (0.0%)4 (3.6%)

41 (37.3%)36 (32.7%)

12 (10.9%)

13 (11.8%)

8 (7.3%)

RESULTS

Physician characteristicsThe medical records reviewed were those of

resident physicians in their second and thirdyears of postgraduate training. During1989-1994, 84 physicians were assigned to theambulatory care clinic. Fifty-three (63%) resi-dent physicians were male, and 31 (37%) werefemale. Sixty-four (76%) of the residents are

self-described as white, 9 (11%) as Asian, 6 (7%)as African American, and 5 (6%) as Hispanic.Patient characteristicsTwo hundred medical records were re-

viewed. Patient characteristics are noted in

Table 1. One hundred ten (55%) women and 90(45%) men were included in the study. Themean age was 64.4 years. The racial distributionof the patient population was 127 (63.5%)African American, 56 (28%) white, 5 (2.5%)Hispanic, and 2 (1.0%) Asian, for 10 (5%) pa-tients, ethnic background was not documented.The insurance status of the patients included 74(37%) with commercial insurance, 66 (33%) withMedicaid or Medicare, and 19 (9.5%) with a

combination of commercial insurance andMedicare. Thirty (15%) were uninsured or self-pay, and 11 (5.5%) did not have their insurancestatus documented. Subgroup analysis revealedthat there was no statistically significant differ-ence between the mean age or insurance statusof the male and female patients. Among AfricanAmerican patients, there were significantlymore females than males (p < 0.04).

Impact of patient genderThe resident physicians performed 85 (42.5%)

rectal examinations, 95 (47.5%) fecal occultblood tests, and 21 (10.5%) flexible sigmoido-scopies on the 200 patients. Analysis of thescreening of the 110 female patients revealedthat 41 (37.3%) had rectal examinations, 43(39.1%) had fecal occult blood testing, and 13(11.8%) had flexible sigmoidoscopies. In the 90male patients, 44 (48.9%) had rectal examina-tions, 52 (57.8%) had fecal occult blood testing,and 8 (8.9%) had flexible sigmoidoscopies. Therewas a statistically significant difference in theperformance of fecal occult blood testing (p <0.008) between male and female patients (Table2). There was no significant difference in the per-formance of colorectal cancer screening based onpatient race or insurance status.

Table 2. Colorectal Cancer Surveillance by Resident Physicians

All patients(n = 200)

Male patients(n = 90)

Female patients(n = 110)

p valueMale vs.

female patientsRectalexaminationsFecal occultblood testingFlexiblesigmoidoscopy

85 (42.5%)

95 (47.5%)

21 (10.5%)

44 (48.9%)

52 (57.8%)

8 (8.9%)

41 (37.3%)

43 (39.1%)

13 (11.8%)

p < 0.008

ns

'ns, not significant.

366 BORUM

Impact of physician genderThe male resident physicians evaluated 134

(67%) of the patients, and the female residentphysicians evaluated 66 (33%) of the patients.This corresponded to the ratio of male/femaleresident physicians participating in the ambu-latory care clinic. Of the 110 women, femalephysicians evaluated 45 (41%) patients, andmale physicians evaluated 56 (50.9%) patients.The remaining 9 (8.2%) patients were seen byboth a male and female resident physician.Analysis of physician gender demonstrated

that female resident physicians performed moreflexible sigmoidoscopies on their patients (p <0.05) than did male resident physicians (Table 3).An assessment of adherence to colorectal cancerscreening guidelines based on patient gender re-vealed that female physicians performed morerectal examinations (p < 0.05) and fecal occultblood tests (p < 0.02) on their female patientsthan did male physicians (Table 4). There was nosignificant difference in the rate that femalephysicians adhered to colorectal cancer screen-ing guidelines between their male and female pa-tients. Male physicians performed statisticallymore (p < 0.004) rectal examinations on theirmale patients than did female physicians (Table5). Additional subgroup analysis showed no sig-nificant difference in the performance of colo-rectal cancer screening based on physician race.

DISCUSSION

Colorectal cancer is a leading cause of can-cer deaths.1 Evidence suggests that colorectal

Table 3. Colorectal Cancer Surveillance in AllPatients (b = 200)a

Female Malephysicians' physicians'performance performancein 66 patients in 120 patients p value

Rectal 32 (48.5%) 54 (45.0%) nsbexaminationsFecal occult 25 (37.9%) 33 (27.5%) nsblood testingFlexible 25 (37.9%) 28 (23.3%) <0.05sigmoidoscopya14 patients were evaluated by both male and female

resident physicians.bns, not significant.

Table 4. Colorectal Cancer Surveillance in FemalePatients (n = 110)a

Female Malephysicians' physicians'performance performancein 45 patients in 56 patients p value

Rectal 22 (48.9%) 16 (28.6%) <0.05examinations

Fecal occult 20 (44.4%) 12 (23.1%) <0.02blood testingHexible 15 (33.3%) 12 (23.1%) nsbsigmoidoscopya9 patients were evaluated by both male and female

physicians.bns, not significant.

cancer screening is a critical component for re-ducing morbidity and mortality. The effective-ness of screening depends on the appropriateapplication of recommended guidelines,2'19 butdata suggest that physicians may inconsis-tently adhere to recommendations.5-10Residency training influences physician

practice patterns. Recent efforts, therefore,have been made to improve education aboutcancer screening guidelines.20'21 Although im-provement can result from the implementationof certain measures, it is crucial to evaluate fac-tors that may affect the use of screening mea-sures.

This investigation suggests that postgradu-ate residency programs should evaluate colo-rectal screening practices by resident physi-cians. Only those patients who were receivinghealth care maintenance were included in thisinvestigation. Those patients who were evalu-

Table 5. Male Resident Physicians' Adherence toColorectal Cancer Surveillance (n = 120)

Female Malepatients patients(n = 56) (n = 64) p value

Rectal 16 (28.6%) 36 (56.3%) <0.004examinationsFecal occult 12 (23.1%) 11 (17.2%) nsablood testingHexible 12 (23.1%) 16 (25.0%) ns

sigmoidoscopyans, not significant.

GENDER MAY INFLUENCE COLON CANCER SCREENING 367

ated for specific medical complaints or whohad clinical indications for a gastrointestinalevaluation were not included in this study. Thepopulation studied thus allowed an assessmentof resident physicians' adherence to cancer

screening guidelines in their ambulatory care

clinic. Potential confounding variables of in-surance status and ethnic background did notinfluence performance of colorectal cancer

screening.Rectal examinations, testing of stool for oc-

cult blood, and flexible sigmoidoscopies were

performed in less than 50% of all patients.Significantly less fecal occult blood testing was

performed on female patients. All residentphysicians were instructed to recommend fecaloccult blood testing in patients >50 years of ageand to document that recommendation in themedical record. There is often concern aboutpatient compliance with fecal occult blood test-

ing. However, in this investigation, there was

correlation between the documentation of fecaloccult blood testing and the completion of thissurveillance technique. In this population, theperformance of fecal occult blood testing ap-peared to be dependent on physician adher-ence to guidelines rather than a function of pa-tient compliance.Although the attending physician super-

vised the resident physicians' decisions, theresident physician had the most direct contactwith patients. The gender of the resident physi-cian, therefore, had the potential to have moreinfluence on adherence to colorectal cancer

screening guidelines than the gender of the at-tending physician. In this resident physicianpopulation, there was no significant differencebetween female and male physicians in con-

ducting rectal examinations and fecal occultblood testing. However, the female residentphysicians performed statisticallymore flexiblesigmoidoscopies on their patients than theirmale colleagues. In addition, female physiciansperformed statistically more rectal examina-tions and fecal occult blood tests on their fe-male patients than did male resident physi-cians. There was no statistical difference in therate that female resident physicians adhered toguidelines in their male and female patients.Although male resident physicians performedstatistically fewer flexible sigmoidoscopies

than female resident physicians, the malephysicians performed significantly more rectalexaminations on their male patients.These results suggest that efforts should be

made to improve screening practices by resi-dent physicians. In addition, patient and physi-cian gender may influence the adherence to co-

lorectal cancer guidelines. Additional researchshould be conducted to evaluate the impact ofgender on cancer screening, and measures

should be taken to ensure gender equity inhealth care.

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Address reprint requests to:Marie Borum, M.D., M.P.H.

The George Washington UniversityMedical Center

Division of Gastroenterology and Nutrition2150 Pennsylvania Avenue, NW

MFA Building, Suite 3-410Washington, DC 20037