biostudies-literatureUnknown33(3)Lundin A<h4>Objectives</h4>This study aimed to examine if the General Health Questionnaire (GHQ)-12 and Kessler 6 (K6) assess the same underlying construct and to develop a score conversion table for the two scales.<h4>Methods</h4>A random sample of 4303 people who completed both the GHQ-12 and K6 in 2021 were analyzed. Exploratory bifactor analysis evaluated if both scales measured the same construct, and Rasch analysis assessed item severities. The scales were transformed using Equipercentile equivalence for comparability and score conversion. Agreement was estimated with Cohen's Kappa coefficient, along with raw positive and negative agreement.<h4>Results</h4>We found that the two scales measure the same phenomenon to the extent that they can be made equivalent. Conversion tables between GHQ-12International journal of methods in psychiatric researche2033https://www.ebi.ac.uk/biostudies/studies/S-EPMC11223604biostudies-literatureMeasuring psychological distress using the 12-item general health questionnaire and the six-item Kessler psychological distress scale. Psychometric comparison and equipercentile equating of the two scales.PMC11223604Ahlen JLalouni MMuwonge JJLundin AfalseMeasuring psychological distress using the 12-item general health questionnaire and the six-item Kessler psychological distress scale. Psychometric comparison and equipercentile equating of the two scales.<h4>Objectives</h4>This study aimed to examine if the General Health Questionnaire (GHQ)-12 and Kessler 6 (K6) assess the same underlying construct and to develop a score conversion table for the two scales.<h4>Methods</h4>A random sample of 4303 people who completed both the GHQ-12 and K6 in 2021 were analyzed. Exploratory bifactor analysis evaluated if both scales measured the same construct, and Rasch analysis assessed item severities. The scales were transformed using Equipercentile equivalence for comparability and score conversion. Agreement was estimated with Cohen's Kappa coefficient, along with raw positive and negative agreement.<h4>Results</h4>We found that the two scales measure the same phenomenon to the extent that they can be made equivalent. Conversion tables between GHQ-122024-01-01T00:00:00Z2024 Sep2025-04-06T00:13:21.373Z2025-04-06T00:13:21.373ZS-EPMC112236043896377210.1002/mpr.2033