Mental health in the military: Pre-Iraq war behavioral health utilization rates, and anonymous survey linkage and combat exposure recall in Operation Iraqi Freedom veterans

Objective. This three-part dissertation studies mental health in United States Active Duty Service Members. The purpose of the first part of this study is to characterize outpatient behavioral health visits in military health care facilities prior to Operation Iraqi Freedom (OIF), including the use of diagnoses outside of the ICD-9 290-319 range, in order to evaluate the overall burden of mental health care. This part of the research establishes baseline rates of mental health care utilization in military mental health clinics in 2000 and serves as a comparison for future studies of the mental health care burden of the current war.;The second part of this study provides a unique application of a procedure to link anonymous survey records as a means to assess mental health problems among soldiers at different time points during the first year after return from deployment to Iraq. The research purpose of the second part is to validate the use of a linkage method on anonymous survey data for longitudinal analysis.;The third part of this study evaluates changes in recall of combat exposures at different time points over the first year after return from deployment. The research purpose of this final part is to utilize the linked datasets to assess whether recall of combat exposures is consistent at different time points; and if not, what demographic and/or PTSD symptom risk factors exist for any directional instability.;Results. The total number of individuals who utilized behavioral health services in 2000 was just over 115 per 1,000 person-years, almost 12% of the military population. Out of every 1,000 person-years, 57.5 individuals received care from behavioral health providers involving an ICD-9 290-319 mental disorder diagnosis, and an additional 26.7 per 1,000 person-years received care in behavioral health clinics only for V-code diagnoses. Attrition from service was correlated with both categories of mental health related diagnoses. After one year, approximately 38% of individuals who received an ICD-9 290-319 mental disorder diagnosis left the military, compared with 23% of those who received mental health V-code diagnoses, and 14% of those who received health care for any other reason (which included well visits for routine physicals).;The second part found final match rates of the surveys to be comparable to rates obtained in preliminary analyses using different methods. The matched records showed very high agreement in variables not included in the matching procedure, and were similar to the unmatched records with regard to demographics and the prevalence of PTSD.;The results of the third part showed a high degree of agreement in combat exposure reporting between the time points, averaging 80-90%. Of the 36 different combat exposure questions, about three-quarters of the respondents had three or fewer changes between the two time points. On average, all three linked datasets showed a similar number of newly endorsed as no longer endorsed exposures. All exposures had weighted kappa statistics between 0.2 and 0.8, with the majority above 0.4.;Conclusions. The first part of the study establishes baseline rates of pre-war behavioral healthcare utilization among military service members, and the relationship of mental health care use and attrition from service. This research indicates that in the military population the burden of mental illness in outpatient clinics is significantly greater when V-code diagnoses are included along with conventional mental disorder diagnostic codes.;The second part of the research demonstrates that use of self-generated codes protects anonymity while the method utilized and validated in this study allows for longitudinal data analysis. The results show that matched surveys were similar to unmatched surveys in terms of demographics and PTSD prevalence.;Finally, the results of the third part demonstrate that over the first year after return from deployment to Iraq, recall of combat experiences remained stable, and that PTSD was slightly associated with increased reporting of combat exposures over time. (Abstract shortened by UMI.).