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Variations in general practitioners' referrals to low-value MRI examinations in Norway: A nationwide register-based
Eivor H Hoff1,2,3, Bjørn M Hofmann4,5, Kristian B Kraft1,6
1Norwegian Institute of Public Health (NIPH), Cluster for Health Services Research, Oslo, Norway.
Background:
Large variations in diagnostic imaging use raise concerns about low-value care, inequity, and inefficient use of resources. Magnetic resonance imaging (MRI) of the head, lumbosacral spine, and knee has been identified as potentially low-value examinations in several clinical contexts.
Objectives:
To examine variation in general practitioners' referrals to low-value MRI examinations in Norway and assess whether differences are associated with GP and practice characteristics.
Methods:
Using national registry data, we linked patients' completed MRI examinations to their regular GP and calculated GP-specific MRI rates per 1000 listed patients. We classified GPs into deciles and compared the characteristics of GPs in the highest (High-10) and lowest (Low-10) referral deciles. We examined predictors of variation using pooled OLS regression models with year fixed effects and GP-clustered standard errors.
Results:
GPs in the top referring decile (High-10) referred patients for potentially low-value MRI examinations at three times the rate of those in the lowest referring decile (Low-10). Experienced (specialist-certified) GPs referred approximately 2.7 fewer examinations per 1000 listed patients per year than less experienced GPs (non-specialists). Shorter consultation times, higher consultation frequency and higher hourly fee income were all associated with higher MRI use - with the strongest association for private MRI. A higher patient disease burden was associated with more total examination, but fewer private examinations per 1000 listed patients per year.
Conclusion:
Referral rates varied markedly between GPs. Specialist-certified GPs had lower rates than non-specialists, and higher activity levels and income from fees were associated with higher referral rates - particularly to private providers.
Insights
General practitioners (GPs) in Norway show significant variation in referring patients for potentially low-value magnetic resonance imaging (MRI) scans. Higher referral rates are linked to factors like GP experience, consultation frequency, and fee income, particularly for private MRI services.
Area of Science:
- Healthcare Management
- Medical Imaging Utilization
- Health Services Research
Background:
- Diagnostic imaging use varies significantly, raising concerns about low-value care, inequity, and resource inefficiency.
- Magnetic resonance imaging (MRI) of the head, lumbosacral spine, and knee are identified as potentially low-value examinations in specific clinical scenarios.
Purpose of the Study:
- To investigate variations in general practitioners' (GPs) referrals for low-value MRI examinations in Norway.
- To assess the association between these referral variations and GP or practice characteristics.
Main Methods:
- Utilized national registry data, linking patient MRI examinations to their regular GP.
- Calculated GP-specific MRI referral rates per 1000 patients and classified GPs into deciles.
- Employed pooled OLS regression models to identify predictors of referral variation, incorporating year fixed effects and GP-clustered standard errors.
Main Results:
- GPs in the highest referral decile referred potentially low-value MRI examinations at three times the rate of those in the lowest decile.
- Experienced (specialist-certified) GPs had lower referral rates compared to less experienced GPs.
- Shorter consultation times, higher consultation frequency, and higher fee income correlated with increased MRI use, especially for private MRI.
Conclusions:
- Significant variation exists in GP referral rates for potentially low-value MRI scans across Norway.
- Specialist certification was associated with lower referral rates, while higher practice activity and fee income correlated with increased referrals, particularly to private providers.
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