Here is the design of a clinical trial:

Official Title: Efecto de Caminar en La prevención de aparición de Insomnio en el Tercer Trimestre de la gestación. Ensayo de Campo Controlado y Aleatorizado

Included conditions:
- Insomnia

Study Armgroups:
- {'label': 'Intervention 1: pedometer', 'type': 'ACTIVE_COMPARATOR', 'description': 'Minimum intervention:\n\n1. Use of pedometer watch from 12 to 32 GW\n2. Recommendations of physical activity', 'interventionNames': ["Device: Pedometer watch 'Xiomi mi band2'"]}
- {'label': 'Intervention 2: pedometer+goal+reminds', 'type': 'EXPERIMENTAL', 'description': 'Maximum intervention:\n\n1. Use of pedometer from 12 to 32 GW\n2. Recommendations of physical activity\n3. Information about get a goal of 11000 steps/day\n4. Reminds the goal every two weeks.', 'interventionNames': ["Device: Pedometer watch 'Xiomi mi band2'"]}
- {'label': 'Control: without pedometer', 'type': 'NO_INTERVENTION', 'description': 'Women receive some recommendations of physical activity during pregnancy. They do not use the pedometer during pregnancy'}

Interventions:
- {'type': 'DEVICE', 'name': "Pedometer watch 'Xiomi mi band2'", 'description': '1. They receive information on the use of the pedometer.\n2. Carry the pedometer (Xiaomi Mi Band 2 ™) from 12 to 32GW.\n3. Prescription of benefits of walking in pregnancy:\n\n   * Receive information about the goal of steps / day to be reached: 10,000-11,000 steps / day (Only the intervention 2 group).\n   * Receive information on the adequacy of walking with moderate intensity.\n4. They will receive messages on the mobile phone remembering the goal to achieve and a notification that the researching staff will proceed to collect the average count of steps / day of the week prior to 20 and 32 gestation weeks (only for the intervention 2 group).', 'armGroupLabels': ['Intervention 1: pedometer', 'Intervention 2: pedometer+goal+reminds']}

Primary Outcomes:
- {'measure': 'Prevalence of Insomnia in third trimester of pregnancy in the three arms with the Insomnia Athens Scale', 'description': 'Insomnia Athens Scale (IAS): An eight-item scale that assesses the quantity and quality of sleep (first five items) and the diurnal repercussion of insomnia (daytime sleepiness, physical and mental functioning and well-being during the day). Each of the items scores from 0 to 3 (affectation of the item from light to severe). The total score ranges from 0 to 24 points, considering insomnia from a score equal to or greater than 6 points (S = 93% and E = 85%) or equal to or greater than 7 points (S = 84% and E = 90%).', 'timeFrame': '32 Gestational Week (GW)'}
- {'measure': 'Change in mean steps/day after intervention in the arms using pedometer', 'description': 'Pedometer register', 'timeFrame': '19 Gestational Week (GW) and 32 GW'}

Please estimate the sample size based on the assumption: 
Alpha error: 5%; Power: 80%; Estimated 20-30% dropout rate.
Sample size
        First, we have carried out the theoretical calculation of the sample size for the definitive study (nâ=â265), based on the following premises: 1) Three study arms: maximum intervention group, pedometer + goal + recall (I1): minimum absolute reduction in the prevalence of low compliance with recommendations that are statistically significant to be detected, that it is 15% with respect to I1; minimum intervention group, pedometer (I2): minimum absolute reduction in the prevalence of low compliance with recommendations that are statistically significant to be detected, that is 30% with respect to C; and control group (C), with an estimated prevalence of low compliance with physical activity recommendations of 50% [12, 13]. 2) Alpha error: 5%; 3) Power of the study: 80%; 4) Comparison of I1 vs I2: from the previous premises, 120 women would be needed in each arm; Comparison of I1 vs C: from the previous premises, and taking as reference the 120 women of the I1 arm required for the previous comparison, 25 women in the C arm would be required.
        A pilot of the previous design was carried out with 72 women not included in this study: 24 women in each arm of the study, interviewed twice (12th and 20th GW), during the months of February to May 2018. The recruitment period was 3Â months. To select a total of 265 women, 1Â year and 7Â months would be required (considering holiday periods and Covid-19). We estimate 20â30% of losses in second and third interviews (due to neonatal loss or abandonment of the study).