Rewarding participants for longitudinal studies
Before collecting data for my study, I've been researching the most effective way to reward of participants for games user research studies that span months and years. Ideally, the reward should entice participants to stay for the entire data collection period.
Note: When I say researching this area, I mean reading the literature and asking user research specialists in academia and industry.
And without further ado, here's the feedback received:
Pay them $30 per hour (and pay weekly)
This was from one of the largest games studios on the planet so they can obviously afford to make it rain for some time. For retaining participants this approach is clearly the winner. Studies back this up showing the higher and more frequent the pay the more likely participants will stay on board.
Pay a lump sum at the end of the study
Whether vouchers or cold hard cash, this give participants something to look forward to. Except there's two problems. For a longitudinal study, the wait could be perceived by participants as too long, leading to gradual de-motivation. Furthermore locking participants into the study through the promise of a large reward could serve to put unnecessary pressure to take part. The result being, participants are more interested payment than providing honest responses.
More optimistic types may be attracted to the potential wins. Those who are risk averse, or want direct compensation for there efforts, won't stay the long haul if they feel they wont get anything for participating.
Improving data collection UX
By being clear on dates and times for activities, making forms quick and easy to use, as well as thanking participants every time they complete a task, you can retain participants without necessarily paying them at all. This approach attracts a certain type of participant. Those highly invested in your topic, or friends and family who want to help out.
Choosing an approach
One main issued when deciding how to collect data for my research. The department simply didn't enough funding to pay participants hourly or an adequate lump sum at the end o the study. They do however, have a small enough pot of money that could be distributed in the form of raffles instead.
The plan now is to enter participants into a daily draw to win a share of the pot of money. If they win the raffle or that day, they get paid the next morning, providing some incentive to come back the day after.
This approach combined with optimising the UX of the data collection process should hopefully trigger a need to continue to the end (essentially acting like a loot-based game).
Will see what happens.