Three hundred seventy-eight individuals were approached for recruitment into one of the six genomic studies; 42 were deemed ineligible or chose not to enroll and were removed from the randomization. A total of 349 experimental consent documents were randomized to 336 individual participants (). Most of the participants were either consenting adult patients or parents or guardians of pediatric patients. Two of the genomic studies (autism and epilepsy) also enrolled patients’ family members to serve as matched case controls. Parents of pediatric patients who enrolled as matched case controls made two consent choices, one for their child who was the primary subject (i.e., parental consent) and one for themselves as a matched case control (i.e., adult/self consent); these cases were treated as a single participant making two distinct decisions (n=13). All participating members of the same family were randomized to the same experimental consent document (n=18 families comprised of 34 individuals making 47 distinct decisions).
Thirteen participants were deemed ineligible: five turned out to have limited English proficiency; four died during the course of the study and could not be debriefed, three were lost to follow up (one participant consented on behalf of a child and as a matched case control for a total of four distinct data release decisions lost to follow up), and one did not provide a data release option. The remaining 323 individual participants were enrolled into the consent study, and 335 distinct data sharing decisions were analyzed.
The median age of participants was 48.5 years old (range 18–86). Most participants were female (57.3%) and non-Hispanic white (56.1%). The majority reported being married (63.7%), Christian (81.3%), and roughly two thirds indicated completing at least one year of college (67.8%) ().
Participant Characteristics by Randomized Consent Type
Consent Type and Data Sharing Decisions
All eligible participants randomized to traditional consent agreed to participate in the genomic study and by default to public release. Most participants (84.9%) randomized to binary consent chose public data release, while the remaining individuals (15.1%) opted out of data sharing (no release). The majority of participants (66.4%) randomized to tiered consent agreed to public data release, less than a fifth (19.5%) chose restricted release, and the remainder (14.1%) chose no release.
Following the debriefing, participants were given an opportunity to change their data release option; the majority (67.8%) stayed with their original choice. Of those who changed, only three chose an option that was less restrictive then their original choice (i.e., changed from no release to restricted release). Those randomized to tiered consent were less likely to change (21.2%) than those randomized to binary (37.7%) or traditional consent (37.9%) (chi-square test, p=0.01).
A majority of participants (53.1%) chose public data release as their final data sharing decision, a third (33.1%) chose restricted release, and the remaining individuals (13.7%) chose no release (). Final data sharing decisions and whether this choice differed from their original selection were significantly associated with randomized consent type (final decision chi-square test, p=.02; changing decision chi-square test, p=.01). Those randomized to traditional consent were most likely to choose public data release as their final data sharing decision (62.1%). Only 6% of participants randomized to traditional consent chose not to release their data at all, compared to nearly 20% of those randomized to either binary or tiered consent. Participants randomized to tiered consent were less likely to change their data sharing decision before and after debriefing. 78.8% of those randomized to tiered consent changed in their final data release selection compared to 62.1% randomized to traditional consent and 62.3% randomized to binary consent.
Pre- and Post-Debriefing Data Release Selections by Randomized Consent Type, Genomic Study and Consentee Relationship
Other Factors Influencing Data Sharing Decisions
Hispanic participants were significantly less likely to choose public data release compared to non-Hispanic white participants (restricted release OR, 2.94; CI, 1.16–7.43; no release OR, 3.94; CI, 1.05–1.76). Unmarried participants, including those who were divorced, widowed, separated, or never married, were more likely to choose restricted data release (OR, 2.40; CI 1.05–5.44). When choosing between restricted and public data release, participants with some college or a college degree were also more likely to choose restricted data release (some college, OR 3.52; CI 1.02–12.14; college graduate, OR 4.67; CI 1.35–16.12) ().
Multinomial Logistic Regression Analysis of Factors Associated with Participants’ Final Data Release Selection
Genomic study was also found to be significantly associated with final data release selection (). Participants from studies conducting pediatric research (autism, brain cancer, and brain control) were more restrictive in their final data release choices than individuals from studies targeting mostly adult populations (liver and pancreatic cancers) (chi-square test, p=.04). To determine if these differences could be categorized based on consentee relationship, parental consent decisions (n=113) were compared with adult/self consent decisions (n=221). Consentee relationship was significantly associated with one’s final data release selection (chi-square test, p<.001). After controlling for other variables, consentee relationship remained a significant predictor; participants providing parental consent were significantly less likely to chose public data release than adults consenting for themselves (restricted release OR, 3.56; CI, 1.57 – 8.08; no release OR, 4.78; CI, 1.46 – 15.64) (). Those participants who made decisions both for themselves (adult/self consent) and on behalf of their child (parental consent) (n=12) made the same data sharing choice for themselves as for their child.
Another possible explanation for the difference between genomic studies could be the amount of time that lapsed between obtaining informed consent and debriefing the study participant. Most of the participants from the autism, brain cancer, and brain control studies were debriefed immediately after the informed consent process, while some individuals from the pancreatic cancer and liver cancer studies were not debriefed until months later (at a subsequent post-operative visit). However, when we controlled for other factors, time lapse between consent and debrief was not found to be a significant predictor of one’s final data release selection (restricted release OR, 1.00; CI, 1.00–1.01; no release OR, 1.00; CI, 0.99–1.01) ().
Refusal and Withdrawal Rates
All of the genomic studies reported high enrollment rates (autism, 85.7%; brain cancer, 80.9%; brain control, 61.5%; epilepsy, 85.7%; liver cancer, 97%; pancreatic cancer, 98.1%). Variations in genomic study enrollment rates were due to individual recruitment methods and the populations under study and were not reflective of issues with the consent process or study or data sharing concerns. Only 20 individuals overall declined participation. Of those, four were randomized to traditional consent, six to binary, three to tiered, and seven were not randomized to a consent type prior to declining. Most who declined participation in the genomic study reported that they did so because of general research-related concerns (e.g., blood draw, no time). Only one participant, randomized to binary consent, specified apprehension about data sharing.