Acute care visits was calculated for each patient as the number of acute care visits over the duration of follow-up (time from enrollment to discontinuation of study participation). Acute visits were identified by manual chart reviews and included hospital admissions, ED, urgent care, day hospital, or infusion center visits. Acute care visits were calculated as the total number of acute care visits reported on study over the years the subject was on study.

All enrolled subjects

Specific item from ASQC-ME QOC. The survey measures patients' self-reported levels of quality of care received. This item was scored on a 10-point scale categorized to three ranges (0-6, 7-8, and 9-10). A "0" value is least, and a "10" value is best. 0-6 indicate the worst care, 7-8 indicate average care, 9-10 indicate the best care. Higher score indicates higher quality of care.

Among participants with survey data available at relevant time points.

Overall patient's perception of their quality of life. Higher quality of life score is better. There are 43 items with 9 dimensions: Pain and Hurt, Pain Impact, Pain Management, Worry I, Worry II, Emotions, Treatment, Communication I, Communication II. Individual questions are scored on a 5-point Likert scale, (0=never, 4=almost always) and scores are transformed on a scale from 0-100, where 0=100, 1=75, 2=50, 3=25, 4=0. If more than 50% of the items are missing, the scale scores should not be computed. If 50% or more items are completed, the mean of the completed items is imputed for the total score.

Participants with data at 6 and 12 months.

Patient's perceived social support score. A higher score for an individual scale or for the overall support index indicates more support. MOS-SSS includes 19 items, with four separate social support subscales and an overall functional social support index. Each item is a 5-level Likert scale (1=None of the time, 5=All of the time). For each of the 4 subscales, respondent-specific mean scores are calculated, ignoring items with missing values. If at least one valid response is is available on a subscale, a score can be received for that subscale. To calculate overall total, take average of item scores for completed items and transform to 0-100 scale (100 is best possible outcome).

Participants who completed the survey.

Patient's readiness to transition scale. A lower score indicates higher readiness. TIP-RFT includes 22 items, with 4 subscales: (1) Independent Living Skills (8 items, range 0-32), (2) Healthcare Knowledge and Skills scale (6 items, range 0-24), (3) Education and Vocational Planning scale (4 items, range 0-16), (4) Social Support Skill set (4 items, range 0-16). For total TIP-RFT, use sum of scales. Total score range (0-88), smaller score is better. If any items were missing, the scores were not computed.

Participants who completed the survey.

Specific item from the Health Care Transition Feedback Survey, created by Got Transition. The survey evaluated patients' experience with changing from a pediatric to an adult approach to care. This question evaluated how often the health care provider explained things in a way that was easy to understand. Answer categories for this item were Always, Usually, Sometimes, and Never.

Participants with survey data at 12 months

Specific item from the Health Care Transition Feedback Survey, created by Got Transition. The survey evaluated patients' experience with changing from a pediatric to an adult approach to care. This question evaluated how often the the patient scheduled their own appointments with their health care provider. Answer categories for this item were Always, Usually, Sometimes, and Never.

Participants with survey data at 12 months

Specific item from the Health Care Transition Feedback Survey, created by Got Transition. The survey evaluated patients' experience with changing from a pediatric to an adult approach to care. This question evaluated if the health care provider updated and shared a medical summary with the patient. Answer categories for this item were Yes or No.

Participants with survey data at 12 months

Ambulatory visits was calculated for each patient as the average number of ambulatory visits per year. Ambulatory visits were identified by manual chart reviews and included primary care visits, visits with the hematology/SCD provider, and other outpatient specialty visits. Ambulatory visits per year was calculated as the total number of ambulatory visits reported over the duration of time on study (from enrollment to discontinuation of study participation).

All enrolled subjects

Adult provider visits was calculated for each patient as the average number of ambulatory visits that occurred with adult providers. These visits were identified by manual chart reviews. Adult provider visits per year was calculated as the total number of adult provider visits reported on study over the time from first visit with adult provider to end of study participation.

Among those with at least one visit with adult provider.

Hospitalization days was calculated for each patient as the average number of days spent inpatient for hospitalization per year. Inpatient dates were identified by manual chart reviews. Hospitalization days per year was calculated as the total number of hospitalization days reported on study over the total duration on study (from enrollment to discontinuation of study participation).

All enrolled subjects

14-day readmissions was calculated for each patient as the number of hospital admissions that occur within 14 days after discharge from a previous admission, per year. Hospital admissions were identified by manual chart reviews and total number of readmissions within 14 days were counted over the duration of time on study.

All enrolled subjects

30-day readmissions will be calculated for each patient as the number of hospital admissions that occur within 30 days after discharge from a previous admission, per year. Hospital admissions were identified by manual chart reviews and total number of readmissions within 30 days were counted over the duration of time on study.

All enrolled subjects