Here is the design of a clinical trial:

Official Title: Incorporating Patient-Reported Outcomes Into Shared Decision Making With Patients With Osteoarthritis of the Hip or Knee

Included conditions:
- Osteo Arthritis Knee

Study Armgroups:
- {'label': 'Joint Insights Decision Aid', 'type': 'EXPERIMENTAL', 'description': 'Participants view the entire Joint Insights decision aid for knee osteoarthritis including: Education Module with information about knee osteoarthritis and risks and benefits of various treatment options, Preferences and Values elicitation questions, and Personalized Risk/Benefit Report.', 'interventionNames': ['Other: Joint Insights decision aid']}
- {'label': 'Education Module Only', 'type': 'ACTIVE_COMPARATOR', 'description': 'Participants view the Joint Insights Education Module only', 'interventionNames': ['Other: Joint Insights decision aid']}

Interventions:
- {'type': 'OTHER', 'name': 'Joint Insights decision aid', 'description': "The Joint Insights decision aid was developed by Dell Medical School faculty in collaboration with OM1, a health outcomes and predictive analytics company. This decision aid uses patient-report outcome measures (PROMs) - specifically, the PROMIS Global and the KOOS JR - along with patient clinical and demographic information (age, sex, race, ethnicity, chronic narcotic use, body mass index), in machine-learning-based predictive analytic models to provide personalized estimates of likely benefit or harm from total knee replacement surgery. The tool is designed to collect PROMs or pull in PROMs collected through other systems (e.g., an EHR or a third-party PROM platform). It also provides condition-specific education to patients with knee OA and allows a patient to reflect on and document their preferences and goals. The personalized risk/benefit report generated by the decision aid is meant to be discussed with the patient's provider to enhance shared decision making.", 'armGroupLabels': ['Education Module Only', 'Joint Insights Decision Aid']}

Primary Outcomes:
- {'measure': 'Patient perception of decision process and quality as measured by the Knee Decision Quality Instrument (Knee-DQI)', 'description': 'Patients are asked about whether they were offered a choice between treatments (yes/no), to what extent the pros and cons were discussed (a lot/some/a little/not at all), and whether the health care provider asked for their preferences (yes/no). Participants receive 1 point for a response of "yes" or "a lot/some." The total points are summed and then divided by the total number of items to result in scores from 0-100%, with higher scores indicated a more shared decision making process.', 'timeFrame': 'Immediately following enrollment visit'}

Please estimate the sample size based on the assumption: 
Type I error rate of 0.05, power of 0.90, equal sample size in intervention and control groups, 10% loss to follow-up rate
Statistical precision and sample size
          We calculated the sample size for the RCT by treating the decision process score of the DQI as continuous. We aimed to detect a treatment effect size (ie, Cohenâs D) as small as 0.5 (consistent with preliminary data from the first 26 subjects we have studied) with a type I error rate of 0.05 and power of 0.90, assuming equal sample size in intervention and control groups. Given our eight randomisation strata, we estimate a needed sample size of 180 participants, or 90 for each group. With an estimated loss to follow-up rate of 10%, our target enrolment for the RCT is 200 participants, or 100 for each arm.