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of their arguments in turn. Their claim that theDOSMD finding of a more favourable course ofschizophrenia in the developing countries may be aproduct of artefacts is based on seven conjectures.

(I) The morefavourable course in the developingcountries could have resulted in part from priortreatment or from continued but unreportedtreatment during the fOllOW-Up.

In seeking support for this hypothesis, Edgerton& Cohen refer to the traditional remedies orunspecified 'drugs' received by 22-460/0 of thepatients in Agra, Chandigarh and Ibadan, and to theone or more applications of electroconvulsivetherapy received by 17% of the Agra patients beforethe first interview, as •• pre-inclusion therapy". Whatthey omit to mention is that the events in questiontook place within the three months preceding theinclusion of these patients into the study, and thatby definition no subject who had had treatmentcontacts before that three-month period was eligiblefor inclusion. In fact, 66% of the patients in thedeveloping countries and 70010 of the patients in thedeveloped countries were included in the study withinone month of their first contact with any helpingagency. The possibility that the outcome ofschizophrenia at two-year follow-up could be biasedby a brief pre-inclusion exposure to herbal medicinesor other unspecified traditional treatments is tooremote to be considered seriously.

(2) The combined cohort attrition rate over thetwo-year follow-up was higher in the developedcountries than in the developing countries. Sincepatients who drop out tend to be healthier than thosewho remain in contact, the reason for a morefavourable course in the developing countries couldhave been the different attrition rates.

While it is true that the two US centres had thehighest attrition rates, while Chandigarh (rural),Agra and Cali had the lowest attrition rates, it is alsotrue that Chandigarh (urban) and Ibadan had higherattrition rates than most of the non-US centres, while

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Dublin had a lower rate. Generally, the difference ,~,

in the attrition rates between the two types of centrefailed to reach the 0.05 level of statistical significance.Moreover, the comparison on eight variables betweenthe patients lost to the follow-up and the patients ti!who remained in the study (Table 4.1 of the WHO ,:'ii.!,

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We welcome Edgerton & Cohen's (1994) highlightof the cross-cultural studies on schizophrenia by theWorld Health Organization (WHO). However, weare concerned that what purports to be amethodological critique of the reports of the twoWHO studies on schizophrenia (the InternationalPilot Study on Schizophrenia - IPSS - and theDeterminants of Outcome of Severe MentalDisorders - DOSMD) is replete with misinterpretations,misquotes, and elementary statistical errors.Edgerton & Cohen question the validity of thermding of a more favourable course of schizophrenicillnesses in the developing as opposed to thedeveloped countries. Having attributed to the WHOmonograph (Jablensky et ai, 1992) "the conclusionthat the putatively more favourable course is aproduct of culture", they go on to "conclude thatthe more favourable course in developing centresmay be a product of artefacts unrelated to cultureas such". We must state that a simplistic explanationof the differences in course and outcome as a"product" or "result" of culture is nowhere to befound in the WHO monograph. Its concludingchapter contains a single reference to 'culture' (ininverted commas) which Edgerton & Cohen quoteout of context and only in part. Since the relevanceof the methodological comments which Edgerton &Cohen advance (pp. 228-229) as a counterargumentto our position hinges on this attribution, wereproduce the paragraph in question in full:

Culture and SchizophreniaCriticisms of WHO studies are answered

A. JABLENSKY, N. SARTORIUS, J. E. COOPER, M. ANKER. A. KORTEN and A. BERTELSEN

"Having excluded, for lack of suppon by the datadescribed in this report, the explanation of the observeddifference between the prognosis of schizophrenia indeveloping and in developed countries as an artefact, astrong case can be made for a real pervasive influenceof a powerful factor which can be referred to as 'culture'.Unfonunately, neither the IPSS nor the Outcome studycould penetrate in sufficient depth below the surfaceon which the impact of this unknown factor wasestablished - tentatively in the IPSS and defInitively inthe present study.... The contribution of the presentstudy, therefore, is not in providing the answer but inclearly demonstrating the existence of the question"(Jablensky et ai, 1992, pp. 88-89).

Since Edgerton & Cohen's paper could be seriouslymisleading to readers who are not familiar with theWHO report, we feel obliged to comment on each

CULTURE AND SCHiZOPHRENIAtorial

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) does not support the notion that those who droptend to have a better outcome. There were onlysignificant differences between the patients lostpatients remaining: the former included a greater

oportion using street drugs (a predictor of poorcome) and the latter included a greater percentage

f lCATEGO S + cases' (no prognostic significance).(3) Eighty included patients did not undergo an

mitial Present State Examination (PSE); 33 ofthemwere in Chandigarh. If the majority of the rest ofthe non-PSE cases were in the developing countries

·it would mean that about 10% ofall the cases in thedeveloping countries had passed different inclusioncriteria from the rest of the sample.

Edgerton & Cohen claim no knowledge of thedistribution ofthe patients who had no initial PSE.But they could easily have found this informationin Table 2.9 of our report, which indicates that 35patients (6.00/0) in the developing countries and 56patients (7.1 %) in the developed countries (i.e. a totalof 91) had for various reasons no PSE on the first

l assessment. Therefore, the imputation of different..~., inclusion criteria to patients in the two types of

setting is unfounded.(4) A higherpercentage ofpatients in the developing

countries reported having had medical problems inthe year preceding inclusion. Schizophrenia-likesymptoms may be the resu/[ of diseases or toxinscommon to developing countries.

We presume the implication is that some of the casesin developing countries might be schizophreniformillnesses caused by a physical disease. Organic cerebalinvolvement (including alcohol- or drug-related braindamage) was an exclusion criterion. Nevertheless, thepossibility of significant physical morbidity underlyingthe acute schizophrenic illnesses was examined in theWHO study and rejected. The detailed distribution isnot reported in the WHO monograph (Edgerton &Cohen are right in pointing out this), but is availableon request. With the exception of malaria, which isendemic in the catchment areas of the developingcountries (13% of the patients in these areas reportedmalaria in the last six ·months), the data are unre­markable and do not suggest an 'organic' explanationof the findings. Malaria, in its cerebral form, isknown to induce acute confusional states and, rarely,a chronic encephalopathy. Neither of these conditionswould have passed the inclusion criteria.

(5) The finding that the more favourable coursein the developing countries is not restricted to thecases of acute onset but is also found in cases ofgradual onset may be artefactual because of thefrequent unreliability ofself-report data on type ofonset, especially when a patient was included aftera lengthy period of illness.

435

Type of onset was a strong predictor of the course,but did not explain fully the differences between thetwo types of centre. One of the key findings was thatwithin the subset of cases with insidious onset ofschizophrenic symptoms, patients in the developingcountries still had better course and outcome thanpatients in developed countries. Conceding that theassessment of mode of onset presents difficulties, theresearch protocol was designed with special attentionto this variable. NotablY, type of onset was not ratedfrom patients' self-reports only, as implied, but wasascertained after structured questioning and cross­examination of a key informant. For most patients(61 %), psychotic symptoms appeared within threemonths of the date of inclusion, and there was nodifference between the patients in developing anddeveloped countries as regards the length of previousillness.

(6) Datafrom Nigeria are omitted from the mostcrucial analyses of course and outcome in theDOSMD study.

This is an incorrect statement. Chapter 4 of theWHO report contains all the data on Ibadan patients'course and outcome: pattern of course (Table 4.2);percentage of follow-up time with psychoticsymptoms (Table 4.3); percentage of follow-up timein remission (Table 4.4); percentage of follow-uptime on antipsychotic medication (Table 4.5);percentage of follow-up time in hospital (Table 4.6);and percentage of follow-up time with unimpairedsocial functioning (Table 4.7). The only tableexcluding Ibadan (because of differences in the ratingscale for mode of onset) is 5.7 in Chapter 5.

(7) Female schizophrenic patients in thedeveloping country centres (Agra excepted) had adramatically better course than male patients. Thisgender difference may account fully for the 10%differential in better outcomes among those withschizophrenia in the developing countries.

Edgerton & Cohen confuse two issues. First, the"10% differential" (also referred to as the"approximately ]0% greater likelihood") is theirarbitrary inference from the reported data, and itdoes not make statistical sense. Apparently, thisinference derives from an out-of-context reading oftwo lines in Table 5.7, which compares thedistributions of the variable 'pattern of course'.However, our conclusion about better outcomes inthe developing countries is based on six differentmeasures of course and outcome (Table 4.10 of thereport), on five of which the percentage differencesbetween the developing and developed countries arefar in excess of 10010.· Secondly, female patients dotend to have a better outcome than males in bothdeveloping and developed countries, and gender is a

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References

that, over time, the symptoms of a proportion ofpatients can be expected to change. The authors seemto confuse here the reliability of psychiatric diagnOSiswith its capacity to predict symptoms.

Conclusion

We believe that "the DOSMD challenge" is real andcannot be explained away as an artefact of datacollection and analysis. Without claiming that OUranalysis and conclusions are either final Orunassailable, we think that the weight of the evidencepoints to consistent differences in the course andoutcome of schizophrenia between developing anddeveloped countries. While no single variable has sofar been identified that would explain the course andoutcome variance across the two types of setting,further analyses of the data, as well as the long-termfollow-up of the DOMSD patients currently inprogress, may reveal effects of multiple factors onthe observed differences in prognosis.

We agree that culture should not be used as asynonym for unexplained variance and that"culturally sensitive" research designs are needed.It is doubtful, however, that either intracultural ornew cross-cultural studies will advance ourunderstanding of the effects of the environment onschizophrenia unless we have testable hypothesesabout specific pathogenetic mechanisms that leadfrom 'culture' to symptoms of schizophrenia.

Discussion of these issues is much needed, especiallyas the enthusiastic embrace of new biologicaltechniques in psychiatry tends to obscure the importanceof the cultural context of psychiatric illness. However,the debate about a complex interdisciplinary issuesuch as culture and schizophrenia can be discredited'in the eyes of readers unless we apply to it standards,of precision and rigour that should be custom andpractice in every scientific discourse.

EDGERTON, R. B. & COHEN, A. (1994) Culture and schizophrenia:the DOSMD challenge, British Journal of Psychiatry, 1.....222-231.

JABLENSKY, A., SARTORIUS, N., ERNBERG, G., et al (1992)Schizophrenia: manifestations, incidence and course in differentcultures. A World Health Organization ten-country study.Psychological Medicine (monograph suppl. 20). '

WORLD HEALTH ORGANIZATION (1979) Schizophrenia. AllIn/emational Follow-up Study. Chichester: Wiley.

JABLENSKY ET AL436

significant predictor of five out of the six measuresof course and outcome. However, we have shownthat this effect is independent of centre, since the log­linear model used in this analysis removes theinteraction effect between centre and gender. We arepuzzled by Edgerton & Cohen's inference (p. 227),apparently based on their own interpretation ofTable 4.8 of our report, that "while a higherpercentage of female patients seem to have a mildcourse in all of the centres, in Cali, Ibadan, andNorth India the average difference between men andwomen comes to + 16.2010", and that "among thedeveloped countries it is only + 5.1070". It seems tous that they have simply averaged horizontally thepercentages in the top rows of Table 4.8 A and Bignoring the fact that these percentages are based ondifferent numbers of subjects. Had they taken thecare to calculate from the data in the table the meanfemale/male percentage difference for pattern ofcourse I (single psychotic episode, complete remission),they would have come up with + 2.9% for Cali, Ibadan,and Chandigarh, and with +17.8% for the developedcountries, exactly the opposite of their claim.

Finally, we wish to correct Edgerton & Cohen'smisinterpretation of the IPSS results. On page 223of their article we read:

"Reliability of diagnosis, too, was problematic.Re-diagnosis at follow-up fOWld that substantial numbersof patients originally diagnosed as schizophrenic indeveloping centres had been misdiagnosed (28010 in Agra,18010 in Ibadan and 28010 in Cali), a phenomenon thatoccurred with similar frequency in only one of the'developed' centres (Moscow)."

Although this statement is not referenced by theauthors, we identified the source for the abovepercentages in Table 6.17 of the IPSS follow-upreport (World Health Organization, 1979). In fact,Edgerton & Cohen quote out of context thepercentages of IPSS patients with an initial diagnosisof schizophrenia who in the course of the two-yearfollow-up developed affective or other psychoticepisodes. For completeness, they should have addedthe percentage for Washington (20%), which ishigher than that for Ibadan. However, the point isthat none of these percentages actually refers to eitherre-diagnosis or misdiagnosis but to an observedchange in symptoms with which the patients presentedon follow-up. It is a commonplace clinical observation

~~;:'A. Jablensky, University Department of Psychiatry, Royal Perth Hospital; N. Sarto~us. Department of:w,Psychiatry, University of Geneva; J. E. Cooper, 25 Ireton Grove. Attenborough, Nottmgham; M. Anker"~iEpidemiological and Statistical Methodology Unit, World Health Organization, Geneva; A. KorteD.,"'''\NH&MRC Social Psychiatry Research Unit, The Australian National University, Canberra; A. 8ertelseD,Aarhus Psychiatric Hospital, Denmark '

Correspoodeoce: A. Jablensky, University Department of Psychiatry, Royal Perth Hospital, 50 Murray Street, PWestern Australia 6000

(Received May /994, accepted May /994)