ArticleAnnals of neurology2013
Confounding underlies the apparent month of birth effect in multiple sclerosis.
Article in Annals of neurology, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 30 papers, 3 of them syntheses 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
30 citing papers in PubMed, 3 syntheses or guidelines pooled it, 59 citations in OpenAlex.
- Season of birth and multiple sclerosis: a systematic review and multivariate meta-analysis.Journal of neurology · 2020Pooled it
- Vitamin D in early life and later risk of multiple sclerosis-A systematic review, meta-analysis.PloS one · 2019Pooled it
- Risk factors associated with the onset of relapsing-remitting and primary progressive multiple sclerosis: a systematic review.BioMed research international · 2015Pooled it
- Integrating Genetics and Environment to Find Causal Mechanisms for Multiple Sclerosis.European journal of immunology · 2026Review
- Global trends in human birth and death seasonality reveal climate-related shifts in reproductive timing.bioRxiv : the preprint server for biology · 2026Article
- The epidemiology, pathology and pathogenesis of MS: Therapeutic implications.Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics · 2025Review
- Differential impact of environmental factors on systemic and localized autoimmunity.Frontiers in immunology · 2023Review
- Multiple sclerosis: Exploring the limits and implications of genetic and environmental susceptibility.PloS one · 2023Article
- Date of birth and the incidence of acute ischemic stroke in Hungary.Revista de neurologia · 2022Article
- Multiple Sclerosis Impact on Pregnancy: An Update on Management Issues : Management of MS During Pregnancy.Galen medical journal · 2022Review
- Evaluation of Month of Birth in Neuromyelitis Optica Spectrum Disorders (NMSOD) and Multiple Sclerosis (MS).Multiple sclerosis international · 2021Article
- Environmental and genetic risk factors for MS: an integrated review.Annals of clinical and translational neurology · 2019Review
- A nationwide survey of the influence of month of birth on the risk of developing multiple sclerosis in Sweden and Iceland.Journal of neurology · 2018Article
- Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis.FASEB journal : official publication of the Federation of American Societies for Experimental Biology · 2017Article
- Gestational bisphenol-A exposure lowers the threshold for autoimmunity in a model of multiple sclerosis.Proceedings of the National Academy of Sciences of the United States of America · 2017Article
- The emergence of neuroepidemiology, neurovirology and neuroimmunology: the legacies of John F. Kurtzke and Richard 'Dick' T. Johnson.Journal of neurology · 2017Article
- Month of birth and level of insolation as risk factors for multiple sclerosis in Poland.PloS one · 2017Article
- Mortality trends of amyotrophic lateral sclerosis in Norway 1951-2014: an age-period-cohort study.Journal of neurology · 2016Article
- Association between seasonal factors and multiple sclerosis.European journal of epidemiology · 2016Review
- Vitamin D Status During Pregnancy and Risk of Multiple Sclerosis in Offspring of Women in the Finnish Maternity Cohort.JAMA neurology · 2016Article
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Authors and funding
6 authors at 2 institutions in 1 country.
Funding
Abstract
objectiveSeveral groups have reported apparent association between month of birth and multiple sclerosis. We sought to test the extent to which such studies might be confounded by extraneous variables such as year and place of birth.
methodsUsing national birth statistics from 2 continents, we assessed the evidence for seasonal variations in birth rate and tested the extent to which these are subject to regional and temporal variation. We then established the age and regional origin distribution for a typical multiple sclerosis case collection and determined the false-positive rate expected when comparing such a collection with birth rates estimated by averaging population-specific national statistics.
resultsWe confirm that seasonality in birth rate is ubiquitous and subject to highly significant regional and temporal variations. In the context of this variation we show that birth rates observed in typical case collections are highly likely to deviate significantly from those obtained by the simple unweighted averaging of national statistics. The significant correlations between birth rates and both place (latitude) and time (year of birth) that characterize the general population indicate that the apparent seasonal patterns for month of birth suggested to be specific for multiple sclerosis (increased in the spring and reduced in the winter) are expected by chance alone.
interpretationIn the absence of adequate control for confounding factors, such as year and place of birth, our analyses indicate that the previous claims for association of multiple sclerosis with month of birth are probably false positives.
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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.