Health and health-care use by New Zealand Vietnam War veterans and their wives : an examination of Andersen's model of health-care utilization : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University
Previous research has found that the debilitating physical and psychological sequelae of combat stress experienced by Vietnam War veterans extend also to their wives. The present study has broadened the focus by applying the Andersen model of health services utilization to health-care used by a community sample of 281 couples comprising New Zealand Vietnam war veterans and their wives who had each completed one postal survey. Andersen (1968) proposed that utilization was a function of three components: predisposition, enablement and physical-need. Predisposition represents sociocultural and personal variables such as ethnicity and health beliefs that increase the likelihood of utilization. Enablement represents familial and medical resources such as income and health insurance which facilitate access health-care. Physical-need represents perceived or diagnosed need for health-care. The present study modified Andersen's model to include two further components, psychological-need and multiple-need. Psychological-need represents variables such as distress and trauma, while multiple-need represents co-existing physical-need and psychological-need. The model was applied to a total of thirteen health-care measures which were categorised as either 'contact' or 'volume' measures Contact measured whether a service had been used, while volume measured the amount of contact with a service. Seven measures tapped professional care (treatment by hospitals, general practitioners (GPs) and other professionals), and six tapped self-care (treatment by prescriptions, bedrest or reduced activity). Although veterans reported greater health-need than their wives, they were less frequent in their use of a range of services, including GP services. Five hypotheses tested core propositions of the model. Results supported one hypothesis; namely, that physical-need was more important in explaining the frequency of GP-service use than the likelihood of its use. The other four hypotheses received either limited or no support. Two hypotheses tested the modified model and received limited support. Psychological-need and multiple-need enhanced the explanation of five and two services, respectively. No evidence was found that poor psychological functioning or co-existing health problems were associated with use of GP services. There was evidence that psychological-need was associated with use of hospital services. Findings suggested that veterans and their wives who did not possess specified enabling resources had impeded access to GP-care. Overall, predisposing characteristics accounted for most of the explained variance across the thirteen measures of health-care, and enabling resources accounted for the least. Discussion focused on the need for future research to refine health-care measures so that the reasons for use or non-use of specific services are explicit, to use longitudinal designs in order to examine the process of health-care, and to more clearly explicate the Andersen (1968) model in terms of theoretical relationships among predictors.