An interventional study of Sustainability added to decision aid in Sustainability, Gallstone and Decision Aid, sponsored by University of Amsterdam. Not yet recruiting at 1 site in Netherlands. Per ClinicalTrials.gov, last updated 2026-04-01.
Sponsored by University of Amsterdam · Not applicable, Interventional, and Treatment
The healthcare sector contributes significantly to climate change. Reducing the number of patients receiving resource-intensive procedures such as surgery can lower carbon emissions, particularly when two treatments with comparable clinical outcomes are available. Nevertheless, the impact of incorporating environmental considerations into patients' decision-making processes remains underexplored. The investigators examine how including information about the environmental impact of treatment options in a gallstone decision aid affects patients' real-life choice between surgery and the more sustainable alternative of conservative treatment. Moreover, the investigators examine whether factors such as severity of symptoms moderate the relation between sustainability information and patients' treatment choice. An exploratory vignette study informed the hypotheses that will be tested among actual patients with gallstones making actual treatment decisions. The results of this ecologically valid study have implications for both clinical practice and healthcare policy by offering insight into the effectiveness of pathways to include patients in the transition towards sustainable healthcare.
199 studies on the registry are indexed under Gallstones; 35 are open to participants now.
This study's planned enrollment of 400 is above the median of 98 across 121 interventional studies indexed under Gallstones.
Browse Gallstones studies →University of Amsterdam is the lead sponsor of 14 studies on the registry; 6 are open to participants now.
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Exclusion Criteria:
Intervention condition, in which a decision aid includes a page with information about the environmental impact of surgical removal of the gallbladder.
Behavioral: Sustainability added to decision aid
A control condition, which includes no information on sustainability in the decision aid.
The intervention decision aid includes a page with information about the environmental impact of surgical removal of the gallbladder, and a control condition, which includes no such information. Besides information about the environmental impact of gallbladder surgery, the intervention and control conditions will be identical. At the end of the decision aid patients will be debriefed in general phrasing (i.e., the aim of this study was to examine which factors affect treatment choice) to prevent influencing the actual decision. Approximately three months after patients received the decision aid, patients will receive an invitation via the PatientPlus portal to complete a survey in which the investigators inquire about their final treatment decision (first reminder after one week, second reminder after two weeks). At the end of this survey, patients will be debriefed about the aim of examining how information about the environmental impact of surgery affects treatment choice.
Treatment preference (surgery or wait-and-see)
The primary outcome is treatment preference. Specifically, participants will indicate their treatment preference by selecting either the option 'Surgery' or 'Wait and see' (dichotomous variable)
Time frame: baseline, pre-intervention
Treatment certainty
Combination of treatment preference and certainty. Treatment certainty will be determined by answering the question 'How sure are you about what you want?' on a scale from 1 (Very uncertain) to 10 (Very certain). Treatment preference\*certainty will be calculated after data collection by multiplying treatment preference (coded as 1 for surgery and -1 for wait and see thus no surgery) with treatment certainty, resulting in a scale from -10 (Very certain about choosing no surgery) to +10 (Very certain about choosing surgery). Adding this continuous measure allows for capturing more nuanced differences between the intervention and control conditions compared to dichotomous measures.
Time frame: baseline, pre-intervention
Treatment decision
Secondary outcome is treatment decision (number of patients that choose surgery and number of patients that choose wait-and-see)
Time frame: Assessment 3 months after the participants receive the decision aid
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Apr 2026; primary completion for Apr 2027, 12 months later.
Of 58 non-industry interventional studies with no phase under Gallstones, half reached primary completion within 20 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 43. This study's planned 12 months is below that.
Counting every sponsor, half of 58 studies reached it within 20 months; a quarter within 12 and three quarters within 43.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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University of Amsterdam