Sonja E. Hall

This paper highlights the uses of population-based linkage of administrative health records to improve the quality, safety, and equity of surgical care. The primary focus of the paper is on the transfer of this type of research into policy and practice. In the modern era of evidence-based medicine, it is essential that not only is new evidence incorporated into clinical practice, but that the implementation and associated costs are monitored; this requires the setting of appropriate benchmarking criteria. Furthermore, it is imperative that all members of the population receive optimal health care and people are not discriminated against because of socio-economic, locational, or racial factors. The use of data linkage can assist with examining these aspects of health care and this paper provides real-life examples such as costs and adverse events from laparoscopic cholecystectomy, event monitoring for post-operative venous thrombosis, and inequalities in cancer care. The influence of these studies on clinical practice and policy is also discussed. Furthermore, this paper discusses the strengths and weaknesses of data linkage research and how to avoid pitfalls. Health researchers, clinicians, and policy-makers will find the discussion of these issues useful in their everyday practice.

OBJECTIVE: To examine the effects of demographic, geographical and socio‐economic factors, and the influence of private health insurance, on patterns of prostate cancer care and 3‐year survival in Western Australia (WA). PATIENTS AND METHODS: The WA Record Linkage Project was used to extract all hospital morbidity, cancer and death records of men diagnosed with prostate cancer between 1982 and 2001. The likelihood of having a radical prostatectomy (RP) was estimated using logistic regression, and the likelihood of death 3 years after diagnosis was estimated using Cox regression. RESULTS: The proportion of men undergoing RP increased six‐fold, from 3.1% to 20.1%, over the 20 years, whilst non‐radical surgery (transurethral, open or closed prostatectomy) simultaneously halved to 29%. Men who had RP were typically younger, married and with less comorbidity. Patients with a first admission to a rural hospital were much less likely to have RP (odds ratio 0.15; 95% confidence interval, CI, 0.11–0.21), whereas residence alone in a rural area had less effect (0.54, 0.29–1.03). A first admission to a private hospital increased the likelihood of having RP (2.40, 2.11–2.72), as did having private health insurance (1.77, 1.56–2.00); being more socio‐economically disadvantaged reduced RP (0.63, 0.47–0.83). The 3‐year mortality rate was greater with a first admission to a rural hospital (relative risk 1.22; 95% CI 1.09–1.36) and in more socio‐economically disadvantaged groups (1.34, 1.10–1.64), whereas those admitted to a private hospital (0.77, 0.71–0.84) or with private health insurance (0.82, 0.76–0.89) fared better. Men who had RP had better survival than those who had non‐radical surgery (4.85, 3.52–6.68) or no surgery (6.42, 4.65–8.84), although this may be an artefact of a screening effect. CONCLUSION: The 3‐year survival was poorer and the use of RP less frequent in men from socio‐economically and geographically disadvantaged backgrounds, particularly those admitted to rural or public hospitals, and those with no private health insurance.

Objective: To examine whether hospital patients with cancer who were identified as Indigenous were as likely to receive surgery for the cancer as non‐Indigenous patients. Design, setting and patients...

The purpose of the present study was to examine the effects of demographic, locational and social disadvantage and the possession of private health insurance in Western Australia on the likelihood of women with breast cancer receiving breast-conserving surgery rather than mastectomy. The WA Record Linkage Project was used to extract all hospital morbidity, cancer and death records of women with breast cancer in Western Australia from 1982 to 2000 inclusive. Comparisons between those receiving breast-conserving surgery and mastectomy were made after adjustment for covariates in logistic regression. Younger women, especially those aged less than 60 years, and those with less comorbidity were more likely to receive breast-conserving surgery (BCS). In lower socio-economic groups, women were less likely to receive BCS (OR 0.73; 95% CI 0.60-0.90). Women resident in rural areas tended to receive less BCS than those from metropolitan areas (OR 0.84; 95% CI 0.55-1.29). Women treated in a rural hospital had a reduced likelihood of BCS (OR 0.74; 95% CI 0.61-0.89). Treatment in a private hospital reduced the likelihood of BCS (OR 0.70; 95% CI 0.54-0.90), while women with private health insurance were much more likely to receive BCS (OR 1.39; 95% CI 1.08-1.79). Several factors were found to affect the likelihood of women with breast cancer receiving breast-conserving surgery, in particular, women from disadvantaged backgrounds were significantly less likely to receive breast-conserving surgery than those from more privileged groups.