Cross-national differences in questionnaires do not necessarily reflect comparable differences in disorder prevalence.
OBJECTIVE
To examine whether the widely used Strengths and Difficulties Questionnaire (SDQ) can validly be used to compare the prevalence of child mental health problems cross nationally.


METHODS
We used data on 29,225 5- to 16-year olds in eight population-based studies from seven countries: Bangladesh, Brazil, Britain, India, Norway, Russia and Yemen. Parents completed the SDQ in all eight studies, teachers in seven studies and youth in five studies. We used these SDQ data to calculate three different sorts of "caseness indicators" based on (1) SDQ symptoms, (2) SDQ symptoms plus impact and (3) an overall respondent judgement of 'definite' or 'severe' difficulties. Respondents also completed structured diagnostic interviews including extensive open-ended questions (the Development and Well-Being Assessment, DAWBA). Diagnostic ratings were all carried out or supervised by the DAWBA's creator, working in conjunction with experienced local professionals.


RESULTS
As judged by the DAWBA, the prevalence of any mental disorder ranged from 2.2% in India to 17.1% in Russia. The nine SDQ caseness indicators (three indicators times three informants) explained 8-56% of the cross-national variation in disorder prevalence. This was insufficient to make meaningful prevalence estimates since populations with a similar measured prevalence of disorder on the DAWBA showed large variations across the various SDQ caseness indicators.


CONCLUSIONS
The relationship between SDQ caseness indicators and disorder rates varies substantially between populations: cross-national differences in SDQ indicators do not necessarily reflect comparable differences in disorder rates. More generally, considerable caution is required when interpreting cross-cultural comparisons of mental health, particularly when these rely on brief questionnaires.
Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK. anna.goodman@lshtm.ac.uk
Anna
A
Goodman
Einar
E
Heiervang
Bacy
B
Fleitlich-Bilyk
Abdulla
A
Alyahri
Vikram
V
Patel
Mohammad S I
MS
Mullick
Helena
H
Slobodskaya
Darci Neves
DN
Dos Santos
Robert
R
Goodman
D000293:Adolescent; D001208:Asia / Q000453:epidemiology; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002653:Child Behavior Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D016001:Confidence Intervals; D003431:Cross-Cultural Comparison; D003625:Data Collection / Q000706:statistics & numerical data; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008603:Mental Health; D010290:Parents / Q000523:psychology; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires