Differences in the use and appreciation of a web-based or printed computer-tailored physical activity intervention for people aged over 50 years.

This study provides insight into the use and appreciation of a tailored physical activity intervention for people aged over 50 years in different intervention conditions (i.e. printed versus web-based and basic versus environmental). Participants (within a clustered randomized controlled trial) received printed or web-based-tailored advice three times within 4 months. Half of the participants also received environmental information. Differences in use and appreciation between both delivery modes and between the basic and environmental condition (similar delivery mode) were assessed at 3 (N = 935) and 6 (N = 649) months after baseline using analyses of variance and chi-square test. The use of the printed intervention (i.e. 92.7-98.2% read, 70.1-76.5% kept and 39.9-56.8% discussed) was significantly higher and printed intervention components were better appreciated than web-based intervention (scores, respectively, 6.06-6.91 versus 5.05-6.11 on a scale of 1-10). In-depth appreciation (e.g. reliability, perceived individualization) was average to high, without differences between intervention conditions. Additional environmental information did not increase appreciation; however, environmental intervention components were more used compared with basic intervention components. Integration of environmental components can stimulate active use of the intervention. To increase the public impact and prevent dropout by participants of web-based physical activity interventions, design modifications are needed for ease of use and improved appreciation.