USING HOME RECRUITMENT TO INCREASE PARTICIPATION AND REPRESENTATIVENESS IN RESEARCH AMONG INDIVIDUALS WITH PSYCHOSIS

• Main Authors: Marianne Haapea, Matti Isohanni, Erika Jääskeläinen, Juha Veijola, Jouko Miettunen
• Format: Article
• Language: English
• Published: The Finnish Foundation for Psychiatric Research 2020-11-01
• Series: Psychiatria Fennica
• Subjects: non-participation; non-response bias; psychosis; recruitment
• Online Access: https://www.psykiatriantutkimussaatio.fi/wp-content/uploads/2020/12/Psychiatria_Fennica-2020_Haapea-et-al..pdf

The participation rates in epidemiologic cohort studies have declined in recent decades. We aimed to evaluate the effect of home recruitment on participation rate and non-response bias within the individuals with psychosis in a follow-up study. The baseline (1999-2001) and follow-up (2008-2010) studies in the Northern Finland Birth Cohort 1966 consisted of magnetic resonance imaging of the brain, cognitive testing and psychiatric assessment. The participation rates were 67% (54/81) for baseline participants, 10% (5/49) for baseline non-participants and 35% (48/136) for those who were diagnosed with a psychosis after the baseline study. In order to increase participation of the individuals who had participated at the baseline (n=81), those who would not have participated otherwise were offered to be interviewed at home. Altogether 18 follow-up participants were home-recruited. Several illness-related variables were compared between the home-recruited participants, standard protocol participants and non-participants. The home-recruited participants had more symptoms, lower functioning, cognition and total grey matter volume, and higher use of antipsychotics measured at baseline (absolute values of effect sizes 0.60-1.05), compared to standard protocol participants and non-participants. The same differences occurred between the home-recruited and standard protocol participants in the follow-up. By using home recruitment we were able to increase the participation rate and to avoid problems of non-response bias. Effective recruitment may need special efforts in population-based studies for individuals with psychosis. Abbreviations: NFBC1966: The Northern Finland Birth Cohort 1966, CRHC: the Care Register for Health Care, PANSS: the Positive and Negative Syndrome Scale, CGI: the Clinical Global Impression, SOFAS: the Social and Occupational Functioning Assessment Scale, MRI: Magnetic Resonance Imaging, TGM: total grey matter volume, CVLT: the California Verbal Learning Test, VOLT: Visual Object Learning Test, AIM: Abstraction, Inhibition and Working Memory task.