The effective start date should be the date the practitioner first became affiliated with the facility. For the initial load period, you may use a default date of 1/1/2000 for practitioners that were affiliated with the facility prior to 1/1/2006. For practitioners whose affiliation began after 1/1/2006, the actual affiliation effective start date should be used. After the initial load period, the actual affiliation effective start and inactive dates should be used.