The titles and abstracts of studies obtained by this search strategy were scrutinized by two reviewers (M.H.B. and A.L.-W.) to determine if they were potentially eligible for inclusion in this review.
Eligibility for the study was based upon scrutiny of the full articles for the following inclusion criteria: 1) the population included in the study had an axis I OCD diagnosis, 2) they were exploratory factor analytic studies of the Y-BOCS or the CY-BOCS and 3) Factor analysis was based on and included at least the 13 main symptom categories of the Y-BOCS. Therefore, for a study to be eligible, it must have included at least the 13 main symptom categories in the Y-BOCS Checklist (seven categories of obsessions: aggression, contamination, sexual, hoarding, religious, symmetry, somatic and six categories of compulsions: cleaning, checking, repeating, counting, ordering, hoarding) or the individual items therein. Studies were included in this meta-analysis if they also included additional symptom categories in their factor analysis such as miscellaneous obsessions and compulsions from the Y-BOCS CL or magical thoughts, superstitious behaviors, rituals involving others from the CY-BOCS CL. Item-by-item factor analyses of the Y-BOCS or CY-BOCS CL were also eligible for this systematic review. Confirmatory factor analyses were not eligible for this review, as they require specification of the models to be tested in advance and so do not compute relationships between the factors uniquely for their data set. Including confirmatory factor analysis in this meta-analysis would bias the results toward the solutions of earlier published studies.
Eligibility for the study was based upon scrutiny of the full articles for the following inclusion criteria: 1) the population included in the study had an axis I OCD diagnosis, 2) they were exploratory factor analytic studies of the Y-BOCS or the CY-BOCS and 3) Factor analysis was based on and included at least the 13 main symptom categories of the Y-BOCS. Therefore, for a study to be eligible, it must have included at least the 13 main symptom categories in the Y-BOCS Checklist (seven categories of obsessions: aggression, contamination, sexual, hoarding, religious, symmetry, somatic and six categories of compulsions: cleaning, checking, repeating, counting, ordering, hoarding) or the individual items therein. Studies were included in this meta-analysis if they also included additional symptom categories in their factor analysis such as miscellaneous obsessions and compulsions from the Y-BOCS CL or magical thoughts, superstitious behaviors, rituals involving others from the CY-BOCS CL. Item-by-item factor analyses of the Y-BOCS or CY-BOCS CL were also eligible for this systematic review. Confirmatory factor analyses were not eligible for this review, as they require specification of the models to be tested in advance and so do not compute relationships between the factors uniquely for their data set. Including confirmatory factor analysis in this meta-analysis would bias the results toward the solutions of earlier published studies.