The K10 is a 10-item questionnaire developed on the basis of item response theory models (Kessler et al. 2002 (link)). It has been used extensively in many countries as part of the World Mental Health Surveys (Andrews & Slade, 2001 (link); Kessler et al. 2002 (link); Furukawa et al. 2003 (link)), although, to date, no validity data have been published from developing countries. A shortened 6-item version of the questionnaire (K6) has also been advocated as a screening measure.
Of the five screening questionnaires, two of which (the K10 and K6) shared six items, most were either already available in local languages (such as the GHQ-12) or in another Indian language (e.g. the K10). Those not available in local languages were translated using the standard, stepwise, method of translation (Sartorius & Kuyken, 1994 ). All questionnaires were piloted to assess feasibility issues, for example on the scoring method. The time duration for reporting complaints varies from 2 weeks in the GHQ-12 to 30 days for the K6/K10. The questionnaires were modified to make them more feasible for use in busy clinics (the GHQ-12 and K10/K6 scoring was made dichotomous) and the duration of reporting symptoms standardized to 2 weeks for all symptoms (as the ICD-10 diagnosis was based on a 2-week duration of symptoms).
The reference standard diagnostic interview was the Revised Clinical Interview Schedule (CIS-R), a structured interview for use by lay interviewers for the measurement and diagnosis of CMD in community and primary-care settings (Lewis et al. 1992 (link)). The CIS-R inquires about the experience of symptoms of CMD in 14 domains (e.g. fatigue, depression, panic). It generates a total score that provides a dimensional measure of CMD. Data can also be analysed using the Programmable Questionnaire System (PROQSY) software program (available from Professor G. Lewis, University of Bristol), which generates ICD-10 diagnoses for the following CMDs: depressive episode, phobias, generalized anxiety disorder, panic disorder, obsessive-compulsive disorders, and mixed anxiety-depression disorder. The CIS-R has been used extensively in India, and specifically in Goa (Sen & Williams, 1987 (link); Patel et al. 1998a (link), b (link), 2003 (link), 2006 (link)). The translation and field testing of the CIS-R in earlier studies in Goa are reported elsewhere (Patel et al. 1998b (link)). We used four case criteria derived from the CIS-R: an ICD-10 diagnosis of any CMD; an ICD-10 diagnosis of depressive episode; a cut-off score of 11/12 (i.e. a score of 12 or more signifying case-level morbidity); and a cut-off score of 17/18 as an indicator of ‘severe’ morbidity.
Of the five screening questionnaires, two of which (the K10 and K6) shared six items, most were either already available in local languages (such as the GHQ-12) or in another Indian language (e.g. the K10). Those not available in local languages were translated using the standard, stepwise, method of translation (Sartorius & Kuyken, 1994 ). All questionnaires were piloted to assess feasibility issues, for example on the scoring method. The time duration for reporting complaints varies from 2 weeks in the GHQ-12 to 30 days for the K6/K10. The questionnaires were modified to make them more feasible for use in busy clinics (the GHQ-12 and K10/K6 scoring was made dichotomous) and the duration of reporting symptoms standardized to 2 weeks for all symptoms (as the ICD-10 diagnosis was based on a 2-week duration of symptoms).
The reference standard diagnostic interview was the Revised Clinical Interview Schedule (CIS-R), a structured interview for use by lay interviewers for the measurement and diagnosis of CMD in community and primary-care settings (Lewis et al. 1992 (link)). The CIS-R inquires about the experience of symptoms of CMD in 14 domains (e.g. fatigue, depression, panic). It generates a total score that provides a dimensional measure of CMD. Data can also be analysed using the Programmable Questionnaire System (PROQSY) software program (available from Professor G. Lewis, University of Bristol), which generates ICD-10 diagnoses for the following CMDs: depressive episode, phobias, generalized anxiety disorder, panic disorder, obsessive-compulsive disorders, and mixed anxiety-depression disorder. The CIS-R has been used extensively in India, and specifically in Goa (Sen & Williams, 1987 (link); Patel et al. 1998a (link), b (link), 2003 (link), 2006 (link)). The translation and field testing of the CIS-R in earlier studies in Goa are reported elsewhere (Patel et al. 1998b (link)). We used four case criteria derived from the CIS-R: an ICD-10 diagnosis of any CMD; an ICD-10 diagnosis of depressive episode; a cut-off score of 11/12 (i.e. a score of 12 or more signifying case-level morbidity); and a cut-off score of 17/18 as an indicator of ‘severe’ morbidity.
