Conduction of individual patient data (IPD) meta-analysis

Supported by the data-management department of the EMGO Institute for Health and Care Research (EMGO+) and by applying high quality standards and procedures, we will create a data sharing infrastructure and a large international database comprising RCTs on (1) physical activity and exercise and (2) psychosocial interventions in cancer patients, in the first two years of the study. 

At present, the basis for the consortium has already been established; various national and international researchers (see consortium) are keen to join the POLARIS consortium, and share their data of randomized controlled trials they conducted. 

Several strategies will be used to establish the collaborative study. Relevant studies will be identified through systematic searches in electronic databases of Medline, EMBASE, CINAHL, PsycINFO, and the Cochrane Database of Systematic Reviews. Other strategies will be personal communication with an international advisory board, trial registers (Dutch trial registry; United States Clinical Trials registry; Current Cobntrolled Trials; WHO clinical trial register; Australian New Zealand Clinical Trials Registry), and via collaborators and/or colleagues.

Study Inclusion Criteria
To be eligible for inclusion in POLARIS, studies have to be randomized controlled trials, physical activity/exercise and/or psychosocial as intervention, wait-list or usual care as control and have (health-related) quality of life included as a primary or secondary outcome measure.

Variables to collect
Variables which we want to collect are identification of patient and centers, baseline characteristics of patients (e.g. age, gender, marital status, diagnosis), characteristics of intervention of interest (i.e. physical activity/exercise and/or psychosocial intervention),  outcome or co-variates of interest (e.g. health-related quality of life, fatigue, physical fitness, distress). The full list of the variables of interest can be found here.


The data from the POLARIS database can be used by consortium members of POLARIS by submitting a paper proposal to the steering committee.