It's a conversation preoccupying cancer researchers: how do we turn around the declining participation in quality of life studies?
Research into the quality of life of cancer patients is in high demand, but until now there has been little attention on how to increase participation.
UNSW researchers have done a systematic review of 311 studies published from 2010 to 2015 that recruited children and adult cancer patients, and parents of children with cancer, for assessments of their quality of life, including depression, anxiety and distress.
The studies were evaluated for the levels of participation achieved, and how the study design impacted on this. The review was published in The Lancet Oncology.
First author Associate Professor Claire Wakefield says the research suggests the best approach is made in person, and shortly after the time of diagnosis.
"You would think that when their treatment is over and patients go back to normal life, this would be the better time to participate in research, but it doesn't seem to work like that," she says.
"And if you send a letter, it's also more likely to be ignored rather than if you make the invitation face-to-face and can explain the research in person."
She says when it comes to questionnaire length, shorter works better, with the review showing that participation dropped with longer questionnaires.
The study also found cancer patients were more likely to want to participate in longitudinal studies, and there was no suggestion that payment or other incentives would motivate them to take part.
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Claire E Wakefield et al. Participation in psychosocial oncology and quality-of-life research: a systematic review, The Lancet Oncology (2017). DOI: 10.1016/S1470-2045(17)30100-6