Methoden vergelijken

	Publicatiebias	P-waarde en statistische significantie
Vakgebied	Onderzoeksstatistiek	Onderzoeksstatistiek
Familie	Process / pipeline	Process / pipeline
Jaar van ontstaan	1979	1925
Grondlegger	Robert Rosenthal	Ronald Fisher
Type	Concept	Concept
Oorspronkelijke bron	Rosenthal, R. (1979). The file drawer problem and tolerance for null results. Psychological Bulletin, 86(3), 638–641.	Fisher, R. A. (1925). Statistical Methods for Research Workers. Oliver and Boyd.
Aliassen	file drawer problem, selective reporting, outcome reporting bias, funnel plot asymmetry	p-value, significance test, statistical significance, alpha level
Verwant	4	5
Samenvatting	Publication bias occurs when the results of a study influence whether the study is published. Typically, studies with statistically significant or positive results are more likely to be published than studies with non-significant or negative results, even if both are scientifically valid. This bias distorts the published literature, making treatments appear more effective than they actually are. Rosenthal (1979) termed this the 'file drawer problem': research with null results sits in file drawers, unpublished, creating a biased sample of published evidence. Funnel plots and statistical tests (e.g., Egger test) can detect asymmetry suggesting publication bias; meta-analyses must account for this bias.	The p-value is the probability of observing data as extreme as or more extreme than what was actually observed, assuming the null hypothesis is true. Introduced by Ronald Fisher in 1925, it is the foundation of frequentist hypothesis testing. Statistical significance is declared when the p-value falls below a pre-specified threshold (alpha level, typically 0.05).