ArticleHealth services research1990
What is too much variation? The null hypothesis in small-area analysis.
Article in Health services research, 1990. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 52 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
52 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Stroke in American Indians and Alaska Natives: A Systematic Review.American journal of public health · 2015Pooled it
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- The Swiss health care atlas-relaunch in scale.Research in health services & regions · 2023Article
- Geographic variation and sociodemographic correlates of prescription psychotropic drug use among children and youth in Ontario, Canada: a population-based study.BMC public health · 2023Article
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- [Regional and gender variations in appendicectomy : Nationwide small-area development of operation rates in the time series].Chirurgie (Heidelberg, Germany) · 2022Article
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- County-level Variation in Low Birthweight and Preterm Birth: An Evaluation of State Medicaid Expansion Under the Affordable Care Act.Medical care · 2020Article
- Utilization and factors associated with antenatal, delivery and postnatal Care Services in Tigray Region, Ethiopia: a community-based cross-sectional study.BMC pregnancy and childbirth · 2020Article
- Regional variation in hospital care at the end-of-life of Dutch patients with lung cancer exists and is not correlated with primary and long-term care.International journal for quality in health care : journal of the International Society for Quality in Health Care · 2020Article
- Patterns of regional variation of opioid prescribing in primary care in England: a retrospective observational study.The British journal of general practice : the journal of the Royal College of General Practitioners · 2018Observational
- Intermediate and advanced topics in multilevel logistic regression analysis.Statistics in medicine · 2017Article
- The median hazard ratio: a useful measure of variance and general contextual effects in multilevel survival analysis.Statistics in medicine · 2017Article
- Adoption of diagnostic technology and variation in caesarean section rates: a test of the practice style hypothesis in Norway.Health services research · 2012Article
- Geographic variation in opioid prescribing in the U.S.The journal of pain · 2012Article
- Geographical variation in certification rates of blindness and sight impairment in England, 2008-2009.BMJ open · 2012Article
- Does access to care affect outcomes of appendicitis in children?--A population-based cohort study.BMC health services research · 2010Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
Abstract
A small-area analysis (SAA) in health services research often calculates surgery rates for several small areas, compares the largest rate to the smallest, notes that the difference is large, and attempts to explain this discrepancy as a function of service availability, physician practice styles, or other factors. SAAs are often difficult to interpret because there is little theoretical basis for determining how much variation would be expected under the null hypothesis that all of the small areas have similar underlying surgery rates and that the observed variation is due to chance. We developed a computer program to simulate the distribution of several commonly used descriptive statistics under the null hypothesis, and used it to examine the variability in rates among the counties of the state of Washington. The expected variability when the null hypothesis is true is surprisingly large, and becomes worse for procedures with low incidence, for smaller populations, when there is variability among the populations of the counties, and when readmissions are possible. The characteristics of four descriptive statistics were studied and compared. None was uniformly good, but the chi-square statistic had better performance than the others. When we reanalyzed five journal articles that presented sufficient data, the results were usually statistically significant. Since SAA research today is tending to deal with low-incidence events, smaller populations, and measures where readmissions are possible, more research is needed on the distribution of small-area statistics under the null hypothesis. New standards are proposed for the presentation of SAA results.
Indexed as
Identifiers
2312306PMC1065599What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.