Use of provincial health insurance plan billing data to estimate carpal tunnel syndrome morbidity and surgery rates

Abstract

Following a work refusal at a plant manufacturing ice cream novelties in Ontario, we were asked to document cases of cumulative trauma disorders (CTDs) and carpal tunnel syndrome (CTS) in this workplace. There were 17 employees with possible hand and wrist problems identified from Workers Compensation Board (WCB) Forms, and from a list prepared at the time of the refusal. After obtaining consents, confirmations of the diagnoses of CTDs, CTS, and of surgical procedures for CTS were obtained from the physicians involved. The relative risk for these disorders among plant employees was estimated in two ways: 1) the rate of CTS operations between 1979 and 1990 was compared to that in the general population using Ontario Health Insurance Plan (OHIP) data on physicians' billings for these operations; and 2) the frequency of WCB first payment claims for tendinitis and CTS during 1987 to 1989 at the plant was compared to that among the entire labor force of Ontario. CTDs had been diagnosed in all 17 workers: 9 had had operations for CTS, but one had had this operation prior to working at the plant. Compared to the remaining 8 workers who had CTS operations, an estimated 0.08 CTS operations would be expected among the 150 employees on the plant's seniority lists between 1979 and 1990, if the estimated rates in the general population were present at the plant, giving a Standardized Morbidity Ratio of 10.0 (95% confidence interval [CI] 4.3-19.7; one-sided p = 2.1 x 10(-6)). There were 6 WCB claims for tendinitis and CTS among plant employees during 1987 through 1989. This frequency was about 68 times that in the entire Ontario labor force (95% CI 24.7-150). This investigation has shown that CTDs, and particularly CTS, documented by medical records, have occurred at least 10 times more frequently than expected at this plant. Use of health insurance billing data to estimate CTS operation rates represents a simple method for estimating the burden of illness at the individual plant level due to CTS (at least for that portion proceeding to surgery), using an objective outcome that can be confirmed from medical records.

Clinical surveillance of carpal tunnel syndrome in two areas of the United Kingdom, 1991-2001

“…In East Kent the early peak in men is clear in the raw patient numbers at 51 years, but the smoothing effect of converting this population to 10 year age bands for age adjustment renders the peak only a modest hump in the age adjusted incidence data. This pattern is essentially similar to that reported for carpal tunnel decompressions in Canada, 16 though with a more pronounced peak in the elderly, but is clearly different from the general portrayal of the age incidence in the wider literature.…”

Capture–recapture estimation of unreported work‐related musculoskeletal disorders in Connecticut

“…Several other studies, however, provide information consistent with this study on the under-reporting of cases to workers' compensation. The studies of Liss et al [1992] and Katz et al [1998] estimate unreported carpal tunnel cases at 1.5±10 times those reported through workers' compensation systems. Further, Maizlisch et al [1995] performed a county-level capture±recapture study of work-related carpal tunnel cases in California.…”

“…These incidence rate estimates derive from US Bureau of Labor Statistics (BLS) surveys [Connecticut Labor Department, 1981±1998, US Bureau of Labor Statistics, 1998Brogmus et al, 1996], from analyses of cases reported through the workers' compensation insurance system [Tanaka et al, 1988;Korrick et al, 1994;Miller et al, 1994;Ashbury, 1995;Frazier and Loomis, 1996], and from physician reporting or health insurance data analysis [Liss et al, 1992;Ekberg et al, 1994;English et al, 1995]. Discussions continue regarding the actual extent of such WRMSD; i.e., the degree to which true incidence is different from the number of reported cases.…”

Symptoms of Musculoskeletal Disorders Among Apprentice Construction Workers

“…(2) Additionally, it has been reported that many MSDs are underreported, raising the number of cases that may actually be occurring in the workplace. (3,4) The nature of work in the construction industry often varies in its work conditions (residential vs. commercial, weather), job sites (workers may work at multiple sites and geographical locations), and employers (workers often have multiple employers). The variable conditions inherent in construction work make it difficult to determine the association between working conditions and MSDs.…”