Expressed demand for healthcare services in regional South Australia: a cross-sectional study

Background Accessibility and availability of health care services/providers is an increasing concern for many regional communities, particularly regional South Australia. However, in order to ascertain the health service/workforce requirements of this community, it is important to understand the health care needs of the population. Assessing the level of health service/provider utilisation within the region (i.e. expressed demand) can be useful in determining both health care need, and health service/workforce demand. This can be helpful for informing future health workforce and health services planning. Methods The regional South Australia health (RESONATE) survey aimed to determine the expressed demand for health care services and the health workforce in a regional South Australian population. The study was open to adults living in regional South Australia and was promoted using a comprehensive multi-modal recruitment campaign. Data were collected between April 2017 and March 2018 using the consumer utilization, expectations and experiences of healthcare instrument, which was administered online and in print. Results 3,926 adults completed the questionnaire. Participants reported using 47 different health care providers in the previous 12 months. Whilst almost all (92.9%) participants had seen a general practitioner in the past 12 months, yoga instructors, chiropractors, pharmacists and physiotherapists were visited most frequently. Services/treatments most frequently received/recommended by a conventional health care provider were prescribed medication (71.9%) and dental procedures (50.4%); and by a complementary medicine provider, massage (26.1%) and vitamin/mineral supplementation (23.0%). Proportionally fewer participants in more remote locations received conventional services/treatments, though a signicantly greater proportion of those in more remote locations had received complementary medicine services/treatments (relative to inner regional areas). Conclusions The ndings of the RESONATE survey point to a high level of expressed demand for conventional and complementary health care services among study participants. Examining the extent to which the health needs of this and other regional populations are met should be the focus of further research to better inform future health workforce/services planning.

Addressing the health care needs of regional communities rst requires an understanding of what those needs are. Examining the prevalence of illness in a population, the level of exposure to risk factors 15 , quality of life and mortality 16 are some of the ways in which heath care need may be determined. Another approach is to assess the level of demand for health care services within a region, which can be reported as either potential demand (i.e. a conveyed need to use a health service) or expressed demand (i.e. actual use of a health service) 15,17 . As expressed demand can be used to measure both health care need and health service utilization, it can be useful in informing health workforce and health services planning 18 .
Regional South Australia hosts some of the highest rates of chronic disease, psychological distress and co-morbidity of any State or Territory of Australia 19 . With a population of 390,645, it is also one of the least densely populated regions in the world 20 , where 23% of the state's population are dispersed across 99.7% of the state (representing a population density of 1 person per 2.52 square kilometres) 21 . Accordingly, regional South Australia serves as a suitable exemplar of a location where potential demand for health services is likely to be high, but accessibility and availability of health services may be problematic. In order to inform future health workforce and health services planning for regional South Australia, we carried out a survey of the population to better understand the expressed demand for health care services in the region.

Methods
Study design: Cross-sectional survey.
Aim & research questions: The Regional South Australia Health (RESONATE) survey was designed to investigate the health care needs of the regional South Australian population, of which there were eight main objectives. For a detailed description of these objectives, see Leach et al 22 . This paper addresses the second objective of the survey: to determine the degree to which health services/treatments were used by adults residing in regional South Australia (i.e. expressed demand). Speci cally, we set out to answer the following questions: 1. What types of health care providers and treatments/services have regional South Australians accessed in the previous twelve months? 2. How frequently have regional South Australians consulted health care providers in the previous twelve months? 3. What mix of health care providers have regional South Australians accessed in the previous twelve months? 4. What sociodemographic factors are associated with the type, frequency and mix of health care providers seen by regional South Australians?
Participants: RESONATE was open to all adults (aged ≥ 18 years) living in a private or non-private dwelling in regional, rural, remote or very remote South Australia, who had used any healthcare service or health intervention in the past 12 months, and had either a xed address (to which a print version of the questionnaire could be dispatched) or internet access (to support completion of the questionnaire online). Participants were also expected to be able to read and understand written English. People with severe visual or cognitive impairment, and those unable to provide informed consent, were not eligible to participate. Based on a target population of 290,290 adults 23 and a ±3% margin of error at the 99% con dence level, we needed to survey at least 1,832 people.
Questionnaire: The tool used for the survey was the consumer utilisation, expectations and experiences of healthcare instrument (CONVERSATIONS) 22  Recruitment and data collection: The study was conducted between April 2017 and March 2018. People were recruited using non-probability (self-selection) sampling, supported by an extensive, multi-modal recruitment campaign. A detailed description of the recruitment strategies utilized in the campaign are reported elsewhere 22 ; in brief, the campaign included the use of assorted online media (e.g. establishment of a project website, organizational email blasts), broadcast media (e.g. television classi ed advertisements, radio interviews), social media (e.g. Instagram and Twitter posts, Facebook advertisements), and print media (e.g. all-household letterbox drop across regional South Australia, newspaper articles). The campaign also included extensive community engagement (e.g. meetings with regional stakeholders, attendance at community events). All recruitment information directed people to either (i) access the project website to acquire additional information and to open the online version of the questionnaire (which was hosted on the SurveyMonkey™ platform, https://www.surveymonkey.com), or (ii) contact the research team to obtain a print version of the questionnaire (and a reply-paid envelope). Data from the completed printed surveys were directly entered into the online survey platform by the research team.
Data analysis: Data from SurveyMonkey™ 24 were imported into IBM® SPSS® Statistics 25.0 25 for cleaning, coding and analysis. The deduplication procedure for online surveys, as described by Konstan et al 26 , was used to manage multiple responses from single participants. The online survey used forcedresponse questions, thus avoiding the need to handle missing data. However, for hard-copy surveys, missing data were simply reported as 'missing'. Categorical data were described using frequency distributions and percentages. Continuous data (which were non-normally distributed) were reported using medians and the interquartile range (IQR). Relationships between ASGC remoteness area and study outcomes were measured using Spearman correlations (for continuous variables) and χ 2 tests (for categorical variables). Correlation coe cients ranging between 0.00-0.29 were de ned as a weak association, 0.30-0.69 as a moderate association, and 0.70-1.00 as a strong association 27 . Distribution of the survey sample was adjusted by applying weights to the age (i.e. by 5-year age group), sex and location distribution (i.e. at the statistical area 3 level) of the regional South Australian population; the purpose of which was to take into account the non-probability sampling strategy. These weights were derived from data obtained through the 2016 Australian population census 28 .

Results
A total of 3,926 adults completed the questionnaire. After adjusting for age, sex and location distribution, the effective sample size was 3,743. As the actual number of people informed about the study could not be ascertained, it was not possible to determine the response rate for the survey.
Demographic characteristics (weighted): The majority of participants were born in Australia (84.2%), aged between 40 and 79 years (66.5%), married (56.1%), employed (51.9%) and living in outer regional South Australia (51.3%) ( Table 1). Almost one-half (43.8%) of participants reported having no/primary/secondary school as their highest level of education, with 40.3% holding a Bachelor degree quali cation or higher. A slightly higher proportion of the study sample were female (52.5%).
Health care provider type: Participants accessed 47 different types of health care providers in the 12 months preceding the survey. The 12-month prevalence of conventional/mainstream service use was 97.9% (3664/3743). Of the 22 distinct conventional/mainstream providers consulted, general practitioners (92.9%), pharmacists (70.5%) and dentists/dental professionals (59.9%) were among the most frequently seen in the preceding 12 months ( Table 2). The conventional/mainstream providers that were least frequently consulted (i.e. by less than 1% of participants) were speech pathologists (0.6%). visited more frequently than any other conventional/mainstream provider ( Table 2). There was a moderate inverse association between ASGC remoteness area and visit frequency with speech therapists (r = -0.440, p = 0.046; i.e. the more remote the participant, the less frequent the provider visits), and a weak inverse association between ASGC remoteness area and visit frequency with physiotherapists (r = -0.136, p < 0.001), podiatrists (r = -0.090, p = 0.012), dentists (r = -0.055, p = 0.009), and medical specialists (r = -0.072, p = 0.002).
Treatment/service type: More than half of participants had received, or were recommended, prescribed medication (71.9%) or a dental procedure (50.4%) by a conventional/mainstream health care provider in the 12 months preceding the survey (Table 4). This was closely followed by prescription eyeglasses (48.3%) and vaccination (42.2%). There was a statistically signi cant association between ASGC remoteness area and some treatment-service types, with participants in more remote locations less likely Around 1 in 4 participants had received or were recommended massage (26.1%) or vitamin / mineral supplementation (23.0%) by a complementary medicine provider in the 12 months preceding the survey ( Table 5). The services least frequently received/recommended by a complementary medicine provider were Tai Chi (1.7%) and pregnancy/birthing support (2.2%). A statistically signi cant association was found between ASGC remoteness area and treatment-service type, with proportionally fewer participants in more remote locations receiving/being recommended Chinese medicine (χ 2

Discussion
This study has generated important insights into the expressed demand for health care services and the health workforce in one of the least densely populated regions in the world-regional South Australia 20 . There was diversity in the type of health care providers accessed and health services received, with almost half of participants choosing to use a combination of both complementary medicine and conventional/mainstream health care providers to address their health care needs. Geographic remoteness appeared to have some bearing on the types of services that participants accessed, with utilization of several complementary medicine providers/treatments shown to be proportionally higher in remote areas versus inner regional locations, whereas the utilization of conventional/mainstream providers/treatments tended to be proportionally lower in remote regions versus inner regional areas.
Overall, there was considerable demand for conventional health care providers among participants, particularly for general practitioners, pharmacists, dentists and opticians/optometrists. The proportion of participants that visited these providers was generally higher than that reported in the general South Australian population (i.e. 93% vs. 88% for general practitioners, and 60% vs. 50% for dentists, respectively) 29,30 . While these distinctions may be partly attributed to differences in the sampling methods of each study, it also might suggest that a proportion of the regional South Australian population have high levels of health care need. Indeed, prevalence rates for conditions such as asthma, cardiovascular disease, arthritis, diabetes, mental illness and osteoporosis have been shown to be much higher in regional South Australia than urban South Australia 19 . A relatively greater prevalence of cataract and dental disease is also reported in regional populations more generally 5,6,[31][32][33] . Similarly, regional South Australians (and regional populations in general) are more likely to be exposed to risk factors associated with these diseases, including higher rates of physical inactivity, smoking, alcohol intake and sugar consumption, and lower intakes of fruit and bre 4,5,9,10,19,34 .
Other factors that may possibly explain the high level of expressed demand for healthcare services among participants are provider over-servicing (i.e. unnecessary healthcare utilization driven by supplierinduced demand) and oversupply (i.e. increased service utilization driven by surplus availability of healthcare resources) 35,36 . There was little indication that the healthcare providers in this sample were over-servicing. In fact, participants generally reported fewer visits to healthcare providers in the preceding twelve months than that reported nationally, including visits to general practitioners (i.e. 4 visits [regional SA] vs. 6.1 visits [Australia]) 29 , dentists (i.e. 2 visits vs. 2.4 visits) 37 and pharmacists (i.e. 4 visits vs. 14 visits) 38 .
The oversupply of healthcare providers was also unlikely to be a driver of the expressed demand for healthcare services in the region, with workforce supply found to be disproportionate to workforce demand in many cases. For instance, nursing, the largest health workforce (which has a providerpopulation ratio of 86/10,000 in regional South Australia) did not rank in the top ve health providers visited by participants 19 . By contrast, one of the smallest health disciplines (opticians/optometrists, which has a provider-population ratio of 0.7/10,000 in regional South Australia), was among the top four most frequently visited health providers in the region 19 . If provider over-servicing and oversupply are unlikely to represent possible explanations for these high healthcare utilization rates, it is probable that the expressed demand for conventional healthcare services in regional South Australia may be driven by healthcare need.
The ndings of this study also point to a moderate level of expressed demand for complementary medicine services among participants. While the types of complementary medicine providers that participants most frequently consulted in the region (i.e. massage therapists and chiropractors) were similar to those most frequented nationally [39][40][41] , the 12-month prevalence rate of complementary medicine service use (i.e. 47%) exceeded that reported in most Australian studies to date (i.e. 27-44%) [39][40][41] . Evidence from previous Australian studies indicates that the higher rates of complementary medicine service use in regional areas (compared to urban areas) may be driven by greater levels of healthcare need, a desire to improve quality of life, dissatisfaction with the outcomes of conventional medical care, and poorer access to conventional healthcare services (including lengthy waiting times) [42][43][44] . Unfortunately, the results of our analysis are unable to substantiate these explanations.
An inverse relationship between remoteness and visit frequency was evident for some conventional and complementary medicine providers, including chiropractors, massage therapists, physiotherapists, speech therapists and traditional Chinese medicine practitioners, and to a lesser extent, dentists, podiatrists and medical specialists. These differences in visit frequency may be explained to some extent by the lower provider-population ratios for some of these disciplines (e.g. dentistry, massage therapy, physiotherapy, podiatry, speech therapy) 19 . For other disciplines, such as chiropractic, there was an inverse relationship between provider-population ratios and visit frequency with increasing remoteness (at least between remoteness area two and remoteness area four) 19 . In this instance, accessibility may be constrained not by provider numbers, but by socioeconomic factors. This is because in Australia, only a limited number of chiropractic services are covered by Medicare (Australia's public health insurance scheme), and only if an individual's general practitioner has endorsed this through a chronic disease management plan or team care arrangement 45 . In other words, if the chiropractic service is not supported by a general practitioner, or the individual requires more than the maximum ve visits per annum, the individual would have to pay for the service out-of-pocket (or via private health insurance), which may be cost-prohibitive for many people living in regional areas.
Access to other complementary medicine services, such as naturopathy, also may be constrained by cost. This is because unlike chiropractic, naturopathy services are not funded by Medicare; instead, these services are paid for out-of-pocket, or until recently, were covered by private health insurance rebates 46 .
Accordingly, access to naturopathy services is likely to be limited to individuals with high incomes and private health insurance 47 . Notwithstanding, our study ndings revealed that the frequency of naturopath visits (unlike other health providers) reported by participants increased as their level of remoteness rose. While this nding could be explained by increased physical access to naturopathic services, this claim cannot be substantiated given the paucity of data on the naturopath workforce in South Australia 48 . However, ndings from a New South Wales study reveal that naturopaths comprise one of the largest groups of complementary medicine providers in rural regions, and in some cases, outnumber the supply of general practitioners 49 .
Treatments/services provided or recommended by health care providers closely re ected the professions most frequently consulted by participants, and thus, most likely re ect the treatments/services that were more readily accessible to participants. For example, prescribed medication, dental procedures and prescription eyeglasses were most likely to have been recommended/provided by a general practitioner/pharmacist, dentist and optician/optometrist, respectively. Similarly, massage therapists and chiropractors were most likely to have recommended/provided massage and spinal manipulation, respectively. Nevertheless, it is not clear as to which complementary medicine providers recommended vitamin/nutrition supplements (the second most frequently recommended complementary medicine treatment), as these are not typically prescribed by massage therapists, chiropractors or yoga instructors in Australia. It is possible that complementary medicine providers working in regional locations may have a broader scope of practice relative to their urban counterparts, not dissimilar to that observed among conventional clinicians working in regional settings 50,51 . Although this represents a reasonable explanation for this situation, it does warrant further investigation.
The RESONATE study represents one of the largest and most comprehensive health surveys ever conducted in regional South Australia. The use of a valid, reliable, acceptable and theoretically-informed questionnaire (i.e. CONVERSATIONS) 22 was an added strength of this research. Notwithstanding, there are some limitations that should be taken into consideration when interpreting the ndings of this research. The use of non-probability sampling suggests the study could be susceptible to self-selection bias. Whilst this risk cannot be eliminated, we did institute several strategies to mitigate this risk, as well as the potential risk of undercoverage bias, recruitment bias and measurement error (e.g. implementation of an extensive multimodal recruitment campaign, widespread community engagement and diverse survey administration methods). These strategies are explained in more detail elsewhere 22 .
Another limitation relating to the use of non-probability sampling is the representativeness of the sample. Although the sex, age and country of birth of participants closely approximated that of the regional South Australian population (based on 2016 Australian population census data) 28 , the sample had less representation from inner regional areas (33.1% vs. 48.3%) and greater representation from outer regional areas (51.3% vs. 39.0%) relative to that reported in the 2016 Australian population census 21 28 . It is possible that the overrepresentation of these groups could impact the conclusions of this study. However, given that these factors are likely to have opposing effects on expressed demand (i.e. higher income and education are generally correlated with greater health care utilization, whereas increasing remoteness and unemployment are typically associated with reduced health care use) [52][53][54] , the extent of this impact remains uncertain.

Conclusions
The RESONATE study has revealed a high level of expressed demand for conventional health care services, and a moderate level of expressed demand for complementary medicine services, among participants living in regional South Australia. This level of demand was considerably higher than that reported in the general South Australian / National population. The implication of this nding is that regional South Australians may have a high level of health care need. The extent to which the health needs of participants have been adequately met however was beyond the scope of this study, and should be the subject of further enquiry to help inform future health workforce and health services planning. Parallel to this work, is a need to further explore the drivers of complementary medicine service utilization in more remote areas, to understand if and how these services may be addressing the health care needs of regional communities. The ndings of this work may help pave the way for the development of more appropriate health service delivery models for regional populations.