urvalsbias
urvalsbias, Swedish for selection bias, refers to systematic errors that occur when the participants or items chosen for a study are not representative of the target population. This bias can arise from various sources such as non‑random sampling, voluntary response, attrition, or researcher expectations influencing inclusion criteria. The result is that findings may systematically overestimate or underestimate true relationships, limiting the external validity of conclusions.
In epidemiological research, selection bias frequently manifests when exposure and outcome data are collected in a
Statistical techniques can mitigate urvalsbias. Randomized designs, probability sampling, weighting adjustments, and sensitivity analyses for missing
Recognizing and addressing urvalsbias is essential to preserve the integrity of scientific research. By systematically evaluating