Reduce the proportion of people with severe hemophilia who have more than 4 joint bleeds each year — BDBS‑01 Data Methodology and Measurement

About the National Data


Baseline: 16.9 percent of persons with severe hemophilia had more than 4 joint bleeds in 2016

Target: 13.3 percent

Number of persons with severe hemophilia with more than 4 joint bleeds in the past 12 months.
Number of persons with severe hemophilia who had a visit in the past 12 months.
Target-setting method
Percentage point improvement
Target-setting method details
Percentage point improvement from the baseline using Cohen's h effect size of 0.10.
Target-setting method justification
Trend data were not available for this objective. A percentage point improvement was calculated using Cohen's h effect size of 0.1. This method was used because no standard error value was available and hemophilia is a rare disease.


Methodology notes

The Registry gathers detailed information on patients who have been seen at federally-funded hemophilia treatment centers (HTCs) since December 2013. HTCs are specialty care centers that receive funding from the Health Resources and Services Administration (HRSA) to provide comprehensive and coordinated diagnosis, treatment, prevention, education, outreach and surveillance services to improve the health of people with genetic bleeding disorders. The Registry includes patients recruited from HTCs located throughout the United States, Puerto Rico and Guam. The Registry collects information on patient characteristics, diagnoses, bleeding events (including bleeding into joints and/or brain), history of inhibitors, treatments (including preventive measures), treatment product use, and the presence of other medical conditions. Severity is defined on the basis of baseline clotting factor activity which is a measure of the person's ability to form normal blood clots. Severe is defined as a baseline clotting factor activity of less than 1% of normal. People who volunteer to participate have medical information collected during routine comprehensive care visits at the HTC. The initial visit form is completed when the patient is enrolled into the study. During this visit, HTC staff collect information about the patient's historic and current clinical information. When the patient returns to clinic for their next comprehensive visit the subsequent visit form is completed. The subsequent visit form collects clinical information and outcomes since the last surveillance visit. The participants represented in the Healthy People 2020 dataset have had at least one subsequent visit form completed. However, because the interval between comprehensive visits may not be exactly 12 months, patients who have visits within three months of the anniversary of their previous visit are eligible for inclusion. The baseline consisted of persons who had an initial visit form completed in December 2013 or calendar year 2014 and had a subsequent visit form that met the eligibility requirement. The data collected are a limited data set that is compliant with the Health Insurance Portability and Accountability Act (HIPPA). The data are collected and transmitted to CDC continuously throughout the year. Joint bleeds are self-reported incidents of bleeding into any join As part of standard of care, patients are trained to identify bleeding into joints as a trigger for early treatment with factor replacement products. Reports of bleeding are ascertained by a variety of methods: paper logs, electronic logs, factor dispensing records, medical chart, routine patient contact (i.e., non-contemporaneous patient verbal report) or other methods. Note: To facilitate ongoing quality improvement, joint bleeding can be further assessed based on demographic characteristics, insurance type, presence of inhibitors and use of preventive treatments, data elements that are also available through the registry.


Comparable HP2020 objective
Retained, which includes core objectives that are continuing from Healthy People 2020 with no change in measurement.

1. Effect size h=0.1 was chosen to correspond with 10% improvement from a baseline of 50%.