Master 2018: all versions of the questionnaire (M-18, P-08, P-13, R-13, S-13) combined
Information on questionnaire versions in particular editions of the POLPAN study
Master 2018: all versions of the questionnaire (M-18, P-08, P-13, R-13, S-13) combined
Information on questionnaire versions in particular editions of the POLPAN study