TY - JOUR AU - Ronksley, Paul E. AU - Tsai, Willis H. AU - Quan, Hude AU - Faris, Peter AU - Hemmelgarn, Brenda R. PY - 2009 DA - 2009/07/15 TI - Data enhancement for co-morbidity measurement among patients referred for sleep diagnostic testing: an observational study JO - BMC Medical Research Methodology SP - 50 VL - 9 IS - 1 AB - Observational outcome studies of patients with obstructive sleep apnea (OSA) require adjustment for co-morbidity to produce valid results. The aim of this study was to evaluate whether the combination of administrative data and self-reported data provided a more complete estimate of co-morbidity among patients referred for sleep diagnostic testing. SN - 1471-2288 UR - https://doi.org/10.1186/1471-2288-9-50 DO - 10.1186/1471-2288-9-50 ID - Ronksley2009 ER -