Analysis
First, we charted the change in the number of visits for anxiety disorders in which an antipsychotic medication was prescribed and considered this change relative to trends in visits in which antidepressants or sedative/hypnotics were prescribed across the same period. We next examined sociodemographic and clinical correlates of antipsychotic prescribing in visits for anxiety disorders. Third, we assessed time trends in antipsychotic medication treatment in visits for anxiety disorders across strata based on clinical and sociodemographic characteristics, adjusting for the effects of other demographic and clinical characteristics.
Analyses were adjusted for visit weights, clustering, and stratification of data using design elements provided by the National Center for Health Statistics. When adjusted for these elements, survey data represent annual visits to U.S. office-based physicians (16). We examined time trends in visits in which antipsychotic medication was prescribed using multivariate binary logistic models. The survey year was transformed by subtracting 1996 from the year and dividing the results by 11. Thus, the transformed value was 0 for the year 1996 and 1 for the year 2007. The odds ratios associated with this transformed variable represent change in the odds of visits in which antipsychotic medication was prescribed across the entire study period. Analyses were conducted using STATA, version 11 (StataCorp., College Station, Tex.).