Maggy Mwangi
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Nurses’ Health Study The Nurses’ Health Study was started in 1976 with 121,700 female registered nurses who were between the ages of 30 and 55. The subjects were surveyed in 1976 and every two years thereafter. The study is ongoing.
Given that this is an observational study, explain which type is it. Whether it is restrospective, cross-sectional or prospective.