Test ordering in an evidence free zone: Rates and associations of Australian general practice trainees' vitamin D test ordering

'Low-value' clinical care in general practice: a cross-sectional analysis of low-value care in early-career GPs' practice

Nonevidence-based and 'low-value' clinical care and medical services are 'questionable' clinical activities that are more likely to cause harm than good or whose benefit is disproportionately low compared with their cost. This study sought to establish general practitioner (GP), patient, practice, and in-consultation associations of an index of key nonevidence-based or low-value 'questionable' clinical practices. The study was nested in the Registrar Clinical Encounters in Training study-an ongoing (from 2010) cohort study in which Australian GP registrars (specialist GP trainees) record details of their in-consultation clinical and educational practice 6-monthly. The outcome factor in analyses, performed on Registrar Clinical Encounters in Training data from 2010 to 2020, was the score on the QUestionable In-Training Clinical Activities Index (QUIT-CAI), which incorporates recommendations of the Australian Choosing Wisely campaign. A cross-sectional analysis used negative binomial regression (with the model including an offset for the number of times the registrar was at risk of performing a questionable activity) to establish associations of QUIT-CAI scores. A total of 3206 individual registrars (response rate 89.9%) recorded 406 812 problems/diagnoses where they were at risk of performing a questionable activity. Of these problems/diagnoses, 15 560 (3.8%) involved questionable activities being performed. In multivariable analyses, higher QUIT-CAI scores (more questionable activities) were significantly associated with earlier registrar training terms: incidence rate ratios (IRRs) of 0.91 [95% confidence interval (CI) 0.87, 0.95] and 0.85 (95% CI 0.80, 0.90) for Term 2 and Term 3, respectively, compared to Term 1. Other significant associations of higher scores included the patient being new to the registrar (IRR 1.27; 95% CI 1.12, 1.45), the patient being of non-English-speaking background (IRR 1.24; 95% CI 1.04, 1.47), the practice being in a higher socioeconomic area decile (IRR 1.01; 95% CI 1.00, 1.02), small practice size (IRR 1.05; 95% CI 1.00, 1.10), shorter consultation duration (IRR 0.99 per minute; 95% CI 0.99, 1.00), and fewer problems addressed in the consultation (IRR 0.84; 95% CI 0.79, 0.89) for each additional problem]. Senior registrars' clinical practice entailed less 'questionable' clinical actions than junior registrars' practice. The association of lower QUIT-CAI scores with a measure of greater continuity of care (the patient not being new to the registrar) suggests that continuity should be supported and facilitated during GP training (and in established GPs' practice).

Health, financial and environmental impacts of unnecessary vitamin D testing: a triple bottom line assessment adapted for healthcare

OBJECTIVE

To undertake an assessment of the health, financial and environmental impacts of a well-recognised example of low-value care; inappropriate vitamin D testing.

DESIGN

Combination of systematic literature search, analysis of routinely collected healthcare data and environmental analysis.

SETTING

Australian healthcare system.

PARTICIPANTS

Population of Australia.

OUTCOME MEASURES

We took a sustainability approach, measuring the health, financial and environmental impacts of a specific healthcare activity. Unnecessary vitamin D testing rates were estimated from best available published literature; by definition, these provide no gain in health outcomes (in contrast to appropriate/necessary tests). Australian population-based test numbers and healthcare costs were obtained from Medicare for vitamin D pathology services. Carbon emissions in kg CO2e were estimated using data from our previous study of the carbon footprint of common pathology tests. We distinguished between tests ordered as the primary test and those ordered as an add-on to other tests, as many may be done in conjunction with other tests. We conducted base case (8% being the primary reason for the blood test) and sensitivity (12% primary test) analyses.

RESULTS

There were a total of 4 457 657 Medicare-funded vitamin D tests in 2020, on average one test for every six Australians, an 11.8% increase from the mean 2018-2019 total. From our literature review, 76.5% of Australia's vitamin D tests provide no net health benefit, equating to 3 410 108 unnecessary tests in 2020. Total costs of unnecessary tests to Medicare amounted to >$A87 000 000. The 2020 carbon footprint of unnecessary vitamin D tests was 28 576 kg (base case) and 42 012 kg (sensitivity) CO2e, equivalent to driving ~160 000-230 000 km in a standard passenger car.

CONCLUSIONS

Unnecessary vitamin D testing contributes to avoidable CO2e emissions and healthcare costs. While the footprint of this example is relatively small, the potential to realise environmental cobenefits by reducing low-value care more broadly is significant.

Did changes to recommended testing criteria affect the rate of vitamin D testing among Australian women

We examine whether new government criteria designed to reduce overuse of vitamin D testing changed testing rates in Australian women. Although testing initially declined, the reduction was not sustained. Women who had more doctor visits and who had been tested previously were more likely to have vitamin D testing.

PURPOSE

Vitamin D testing increased substantially in the 2000s in many countries, particularly in women. Because of concerns about potential over-testing, in 2014, the Australian criteria for subsidised testing were restricted to those at high risk of vitamin D deficiency. We aimed to describe vitamin D testing trends in Australian women (1996 to 2019) and investigate sociodemographic and health factors associated with testing under the new criteria.

METHODS

We used joinpoint regression to assess changes in national testing trends in Australian women (aged 15+ years) using universal health insurance system data. Additionally, we investigated the factors associated with vitamin D testing through Poisson regression with robust error variance using survey and linked insurance system data from participants born 1946-51 in the Australian Longitudinal Study on Women's Health (ALSWH).

RESULTS

Between 1996 and 2013, vitamin D testing rates increased in all age groups. Rates declined between 2013 and 2016, but increased again between 2016 and 2019. In the ALSWH cohort, a higher likelihood of testing under the new criteria was associated with 12 or more doctor visits per year compared to two or fewer visits per year (relative risk (RR) 1.85; 95% CI 1.61-2.12), and women who had two or more vitamin D tests between 2012 and 2014 compared to no test (RR 1.55; 95% CI 1.48-1.62).

CONCLUSION

The introduction of new criteria has not led to sustained declines in testing. High testing rates and repeated testing suggest that over-testing for vitamin D deficiency in Australian women is still occurring.

Changes to the frequency and appropriateness of vitamin D testing after the introduction of new Medicare criteria for rebates in Australian general practice: evidence from 1.5 million patients in the NPS MedicineInsight database

OBJECTIVES

To assess changes in the frequency of vitamin D testing and detection of moderate/severe vitamin D deficiency (<30 nmol/L) among adults after the introduction of new Medicare Benefits Schedule (MBS) rebate criteria (November 2014), and their relationship to sociodemographic and clinical characteristics.

DESIGN

Dynamic (open) cohort study SETTING: Primary care PARTICIPANTS: About 1.5 million 'active' patients aged 18+ years visiting a general practitioner and included in the National Prescribing Service MedicineInsight database.

OUTCOME MEASURES

The frequency of vitamin D testing (per 1000 consultations) and moderate/severe vitamin D deficiency (%) recorded between October 2013 and March 2016, stratified by the release of the new MBS criteria for rebate.

RESULTS

More patients were female (57.7%) and 30.2% were aged 60+ years. Vitamin D testing decreased 47% (from 40.3 to 21.4 tests per 1000 consultations) after the new MBS criteria, while the proportion of tests with no indication for being performed increased from 71.3% to 76.5%. The proportion of patients identified as moderate/severe vitamin D deficient among those tested increased from 5.4% to 6.5%. Practices located in high socioeconomic areas continued to have the highest rates of testing, but moderate/severe vitamin D deficiency detection remained 90% more frequent in practices from low socioeconomic areas after the rebate change. Furthermore, the frequency of individuals being tested was reduced independent of the patients' sociodemographic or clinical condition, and the gap in the prevalence of vitamin D deficiency detection between those meeting or not meeting the criteria for being tested remained the same. Moderate/severe vitamin D deficiency detection decreased slightly among patients with hyperparathyroidism or chronic renal failure.

CONCLUSIONS

Although the new criteria for rebate almost halved the frequency of vitamin D testing, it also lessened the frequency of testing among those at higher risk of deficiency, with only a small improvement in vitamin D deficiency detection.

Investigating causality in the association between vitamin D status and self-reported tiredness

Self-reported tiredness or low energy, often referred to as fatigue, has been linked to low levels of circulating 25-hydroxyvitamin D (25OHD), a biomarker of vitamin D status. Although it is uncertain if the association is causal, fatigue is a common indication for testing, and correcting, low 25OHD-levels. We used two-sample Mendelian randomization to test for genetic evidence of a causal association between low 25OHD-levels and fatigue. Genetic-25OHD associations were estimated from the largest genome-wide association study of vitamin D to date, and genetic-fatigue associations were estimated in 327,478 individuals of European descent in UK Biobank, of whom 19,526 (5.96%) reported fatigue (tiredness or low energy nearly every day over the past two weeks). Using seven genome-wide significant 25OHD-reducing genetic variants, there was little evidence for a causal effect of 25OHD on fatigue (odds ratio for fatigue was 1.05 with 95% confidence interval of 0.87–1.27 per 1-SD decrease in log-transformed 25OHD). There was also little evidence of association between any individual 25OHD-reducing variant and fatigue. Our results suggest that a clinically relevant protective effect of 25OHD-levels on fatigue is unlikely. Therefore, vitamin D supplementation of the general population to raise 25OHD-levels is not likely to be useful in preventing fatigue.

Clinical Management of Low Vitamin D: A Scoping Review of Physicians' Practices

The role of vitamin D in the prevention and treatment of non-skeletal health issues has received significant media and research attention in recent years. Costs associated with clinical management of low vitamin D (LVD) have increased exponentially. However, no clear evidence supports vitamin D screening to improve health outcomes. Authoritative bodies and professional societies do not recommend population-wide vitamin D screening in community-dwelling adults who are asymptomatic or at low risk of LVD. To assess patterns of physicians’ management of LVD in this conflicting environment, we conducted a scoping review of three electronic databases and the gray literature. Thirty-eight records met inclusion criteria and were summarized in an evidence table. Thirteen studies published between 2006 and 2015 across seven countries showed a consistent increase in vitamin D lab tests and related costs. Many vitamin D testing patterns reflected screening rather than targeted testing for individuals at high risk of vitamin D deficiency or insufficiency. Interventions aimed at managing inappropriate clinical practices related to LVD were effective in the short term. Variability and controversy were pervasive in many aspects of vitamin D management, shining a light on physicians’ practices in the face of uncertainty. Future research is needed to inform better clinical guidelines and to assess implementation practices that encourage evidence-based management of LVD in adult populations.

Considerations for Secondary Prevention of Nutritional Deficiencies in High-Risk Groups in High-Income Countries

Surveys in high-income countries show that inadequacies and deficiencies can be common for some nutrients, particularly in vulnerable subgroups of the population. Inadequate intakes, high requirements for rapid growth and development, or age- or disease-related impairments in nutrient intake, digestion, absorption, or increased nutrient losses can lead to micronutrient deficiencies. The consequent subclinical conditions are difficult to recognize if not screened for and often go unnoticed. Nutrient deficiencies can be persistent despite primary nutrition interventions that are aimed at improving dietary intakes. Secondary prevention that targets groups at high risk of inadequacy or deficiency, such as in the primary care setting, can be a useful complementary approach to address persistent nutritional gaps. However, this strategy is often underestimated and overlooked as potentially cost-effective means to prevent future health care costs and to improve the health and quality of life of individuals. In this paper, the authors discuss key appraisal criteria to consider when evaluating the benefits and disadvantages of a secondary prevention of nutrient deficiencies through screening.