Using Inferred Mobility Status to Estimate the Time to Major Depressive Disorder Diagnosis Post-Spinal Cord Injury.

This was a retrospective administrative claims study, not a clinical trial or chart review, so it cannot show that any factor caused major depressive disorder. Major depressive disorder was identified from ICD-9 codes or antidepressant claims, which can miss undiagnosed or untreated depression and can misclassify antidepressants prescribed for pain. The study did not measure depressive symptom severity, injury severity, or functional mobility directly. Inferred mobility status came from durable medical equipment claims, not from what equipment was actually issued, used, or obtained without insurance. Rehabilitation service claims were not separated by discipline, so the study cannot say whether physical, occupational, or speech therapy specifically was associated. The sample was limited to employer-sponsored insurance and ages 16 to 64, so results may not apply to Medicare, Medicaid, uninsured, or older adults. Some diagnoses or claims may have occurred outside the study time frame, and coding errors or coding practice changes could have affected results. The paper cited a positive predictive value of 66% and negative predictive value of 77% for Medicare depression claims, showing claims may not perfectly identify clinical criteria.

The authors declare no conflicts of interest. One author received a Promotion of Doctoral Studies (PODS I) Scholarship from the Foundation for Physical Therapy Research. The article is also labelled as supported by NIH extramural research.

Do not conclude that rehabilitation services, power wheelchair use, or mobility impairment cause major depressive disorder after spinal cord injury. The study used insurance claims and an inferred mobility proxy, did not measure symptoms or severity, and reported associations that may reflect injury severity, discharge needs, or other unmeasured factors.