Here is the design of a clinical trial:

Official Title: A Telehealth-based Cognitive-adaptive Training for Women With Breast Cancer in Risk to Suffer Cancer and Chemotherapy-related Cognitive Impairment: a Randomized Controlled Trial.

Included conditions:
- Breast Neoplasms

Study Armgroups:
- {'label': 'e-OTCAT', 'type': 'EXPERIMENTAL', 'description': 'The experimental group will receive the e-OTCAT program that consists of a 12-week videoconference-based occupational therapy intervention at the same time women with breast cancer receive chemotherapy.', 'interventionNames': ['Other: e-OTCAT program']}
- {'label': 'Control Group', 'type': 'OTHER', 'description': 'At the beginning of chemotherapy, the participants allocated to the control group will only receive an educational handbook containing information about most frequent side-effects of cancer and cancer treatments, plus standard care for these patients.', 'interventionNames': ['Other: Educational handbook and standard care']}

Interventions:
- {'type': 'OTHER', 'name': 'e-OTCAT program', 'description': 'The e-OTCAT program consists of a combination of cognitive training in terms of attention, memory and processing speed; and adaptive training based on metacognition and cognitive-behavioral strategies (psycho-education, relaxation techniques training, stress management, energy conservation techniques, time management, etc.).\n\nThis program also includes homework exercises consisting of a handbook of paper-and-pencil exercises, a cognitive training mobile app, and the practice of strategies seen in adaptive training sessions.', 'armGroupLabels': ['e-OTCAT']}
- {'type': 'OTHER', 'name': 'Educational handbook and standard care', 'description': 'At the beginning of chemotherapy, the participants will receive an educational handbook containing information about most frequent side-effects of cancer and cancer treatments, plus standard care.', 'armGroupLabels': ['Control Group']}

Primary Outcomes:
- {'measure': 'Subjective cognitive Function:', 'description': 'The primary outcome will be assessed with the Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog) will be used to assess the subjective cognitive functioning.', 'timeFrame': 'Participants will be followed over 6 months'}

Please estimate the sample size based on the assumption: 
alpha error of 0.05, a power of 85%, and a 10% dropout rate
2.6. Sample Size
        The sample size for cognitive function was calculated based on a similar previous study using FACT-Cog version 3.0 [43]. Assuming an alpha error of 0.05, a power of 85% and a medium effect size (d = 0.58) based on the results of the reference study, we need a sample of 44 participants for each group (G*Power v.3.1). In order to compensate for a possible 10% dropout rate [44], we will recruit a total of 98 participants (49 per group).