Here is the design of a clinical trial:

Official Title: Association Between Gait Features Assessed by Artificial Intelligent System and Cognitive Function Decline in the Patients of Silent Cerebrovascular Disease: A Multicenter Prospective Cohort Study

Included conditions:
- Silent Stroke

Study Armgroups:
- {'label': 'positive', 'description': 'Subjects have gait disorder according to intelligent gait assessment at baseline.', 'interventionNames': ['Other: there is no intervention']}
- {'label': 'negative', 'description': "Subjects don't have gait disorder according to intelligent gait assessment at baseline.", 'interventionNames': ['Other: there is no intervention']}

Interventions:
- {'type': 'OTHER', 'name': 'there is no intervention', 'description': 'There is no intervention', 'armGroupLabels': ['negative', 'positive']}

Primary Outcomes:
- {'measure': 'Change in cognitive assessment scale score(MMSE)', 'description': 'It will be assessed by the Mini-Mental state examination (MMSE), which is scored 0-30.', 'timeFrame': '1 year'}

Please estimate the sample size based on the assumption: 
Test efficiency (1-beta) is 90%, test level (alpha) is 0.05, and an estimated 20% shedding rate.
Sample size
        Referring to previous studies of cognitive decline among patients with SCD [19â23], we assume that the MMSE score will decrease by 0.5âÂ±â0.5 points in the normal gait group and 0.7âÂ±â1.2 points in the abnormal gait group within 1âyear; the ratio of abnormal gait to normal gait among outpatients with SCD is 1:2. Test efficiency 1-beta is set at 90%, while test level alpha is set at 0.05. An estimated 20% shedding rate, sample size of 1050 patients with a normal gait and 550 patients with an abnormal gait will be required. Therefore, a total of 1600 patients will be included.