Affiliation with a primary care provider in New Zealand: Who is, who isn’t

Abstract

Aims

New Zealand has a mixed public–private funded primary care system. In the last decade, considerable effort has gone into reducing the financial barriers to primary care, with some targeting of greater public funding of practices in more deprived areas. In this paper we explore the association of socio-demographic factors with affiliation with a primary care provider (PCP), and specifically examine the association with deprivation. Affiliation refers to having a doctor, nurse or medical centre one could go to if need arises.

Methods

We used data from the third wave (2004–2005) of an ongoing 8-year panel study of 22,000 adults that includes a health add-on. This paper utilises demographic, socio-economic and health behaviour characteristics of those who reported affiliation with a PCP at wave 3. Affiliation itself was measured with the question: “do you have a doctor, nurse or medical centre you usually go to, if you need to see a doctor?” Logistic regression is used to determine the independent association of a range of socio-demographic factors with affiliation with a PCP.

Results

Of the total of 18,320 respondents, 1530 (8.3%) reported no affiliation with a PCP. The odds of affiliation was significantly lower for males compared to females (OR 0.45, 95% CI: 0.39–0.50), never married compared to currently married (OR 0.48, 95% CI: 0.41–0.57), Asians compared to New Zealand Europeans (OR 0.47, 95% CI: 0.38–0.57), current smokers compared to never smokers (OR 0.79, 95% CI: 0.68–0.91) and those with post-school education compared to no education (OR 0.65, 95% CI: 0.55–0.76) and higher for older adults aged 65 years and over compared to young adults aged 15–24 years old (OR 5.14, 95% CI: 3.59–7.36), those reporting poor self-assessed health compared to those reporting good health (OR 1.45, 95% CI: 1.06–1.98), and those reporting one or more co-morbid conditions compared to no co-morbid conditions (OR 2.02, 95% CI: 1.78–2.29). However, there was no significant difference in affiliation with a PCP between those living in the most deprived areas and the least deprived areas.

Conclusions

Affiliation to a PCP is a measure of potential access to primary care. Overall, our data provide some support for the hypothesis that people with high health needs have high rates of affiliation with a PCP (e.g., elderly, women, Māori and those in poor health). The results also suggest that current health policies in New Zealand, with their emphasis on a strong primary health care system, are ensuring that people with greater health care needs are affiliated with a PCP.

Introduction

There is a well-established body of international evidence that suggests that high quality primary care is important for improving health outcomes, controlling health care spending, and reducing health care disparities [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13]. Affiliation, which refers to having a usual source of care (doctor, nurse or medical centre) or primary care provider (PCP) one could go to if need arises, is considered to be one of the four critical features of primary care [14]. Affiliation with a PCP or “having a regular source of care” has been considered both a measure of access and a determinant of access in health services research. Aday et al. [15], [16], [17] treat having a regular source of care as a structural component of the health care system that demonstrates an individual's uninhibited entry into the system. However, others have also considered regular source of care as a determinant of access [14].

Defining the characteristics of those not affiliated with a PCP at the individual level is especially important in the light of the fact that a PCP is usually the first point of contact for patients, and PCPs are “gatekeepers” who regulate access to more costly secondary and tertiary care. Affiliation with a PCP does not necessarily mean actual utilisation of primary care services. Rather, following Aday et al. [15], [16], [17], this study uses it is as a measure of potential access that makes it more likely that care will be used [18], [19], [20], [21].

Studies, mainly from the US, have shown that potential access – having a regular provider of care – is strongly related to the likelihood of seeing a physician [15], [16], [22]; is one of the strongest predictors of access to health care services [17], [23]; has been associated with greater use of preventive health services [24], [25], [26] and with fewer emergency department visits [27]. In addition, some studies have also reported that having potential access is also associated with 25% lower total costs of care compared with those not having regular source of primary care [28], and with greater satisfaction with the health care received [15]. The influence of having a usual source of care seems to grow as use becomes more discretionary [18], [22]. For example, in the US Rundall and Wheeler found that the presence or absence of a usual source of care was more important than income in predicting use of preventive services among a sample of adults [22].

There is considerable policy interest in defining the characteristics of people who are affiliated/not affiliated with a PCP. First, there is evidence from the US that those not having a regular health care provider are more likely to rely on hospital outpatient and emergency departments as a regular source of care. This may increase costs to the publicly funded health care system [16], [29]. Second, research has also shown that people who use hospitals or emergency departments as the usual source of care face more substantial barriers to access to physicians [18] and have few alternatives to outpatient care [30], [31], [32], [33], [34], [35]. Many walk-in patients leave the emergency department without being seen because of long waiting periods [30], [31]. Third, persons who lack a regular source of care are more likely to experience delays in seeking preventive health care services [24], and are therefore at greater risk of chronic health conditions. If not having a regular provider of care is related to substantial barriers to receiving care and increased use of emergency departments in hospitals for non-emergency or minor problems, as some research suggests, then one strategy to improve access, quality of health care and reduce costs may be to promote affiliation with a PCP.

The objective of this study is to use national survey data to determine who is affiliated with a PCP in New Zealand. The specific aims of the study are to explore: (1) the demographic, (2) socioeconomic and (3) health behaviour and health characteristics of people who are affiliated/not affiliated with a PCP. We hypothesise that after adjusting for demographic, socio-economic and behavioural factors, those who have a greater need are more likely to be affiliated with a PCP. While identification of subgroups who are affiliated/not affiliated with a PCP is of interest in its own right, it is particularly important in the New Zealand context, mainly because the 2001 New Zealand Primary Health Care Strategy aims to reduce inequalities in health and ensure greater access to and use of preventive health services [36]. Secondly, the bulk of research on this area has been carried out mainly on European and American data and it is important to examine this issue outside the US and Europe to see whether the pattern established there applies elsewhere.

New Zealand has a largely tax-funded health system which, in its general form, looks similar to the United Kingdom's National Health Service, including its foundation of GP based primary health care. Yet New Zealand is unusual among welfare states of the liberal democratic model because primary health care is only approximately 60% funded by government [37]. Because of patient co-payments, the paucity of indigenous (Māori) and Pacific Islanders in the primary health care workforce [38], and the uneven distribution of GPs, significant financial, cultural and geographical barriers to access exist for primary health care in some parts of the country [39], [40], [41].

New Zealand's current Primary Health Care Strategy [36], released in 2001, aims to address some of these access barriers. The central feature of the strategy is the grouping of the primary care providers (general practitioners (GPs), primary care nurses and other health professionals such as Māori health providers and health promotion workers) into networks called Primary Health Organisations (PHOs). While joining a PHO was voluntary, primary care providers were encouraged to do so by more generous and regularly increasing subsidies paid to PHOs in line with the Consumer Price Index (CPI). PHOs are funded on a capitation basis for providing a specified set of treatment and preventive services to their enrolled populations regardless of whether contact is made during the period [42], [43], [44]. Two different PHO types (Access and Interim) were developed. ‘Access’ PHOs were those organisations that had an enrolled population with more than 50% identified as high need as determined by deprivation (those living in the two most socioeconomically deprived deciles) and ethnicity (Māori and Pacific). All other PHOs were ‘Interim’. In order to make the biggest difference to those in greatest need, the higher subsidy rates were initially paid to people enrolled in Access PHOs. However, the intention of the government was to roll out similar levels of funding to all PHOs and to include both GP services and pharmaceuticals. Higher subsidy rates included all age groups by July 2007. As a result of increased subsidies, the levels of co-payments for primary care have reduced substantially. For those who were previously not subsidised at all, GP charges have fallen from an average of $50 per GP visit to $25 or less, and some services are provided free of charge [45]. However, during the period under study higher subsidy rates were not applicable to those aged between 25 and 64 in Interim PHOs.