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Design of healthy hearts in the heartland (H3): A practice-randomized, comparative effectiveness study
Jody D Ciolino1, Kathryn L Jackson2, David T Liss3
1Department of Preventive Medicine, Division of Biostatistics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Insights
The Healthy Hearts in the Heartland study tested Point-of-Care (POC) and POC plus Population Management (POC+PM) strategies to improve cardiovascular health measures in primary care practices. The study design successfully balanced baseline characteristics, with final outcome analyses pending.
Area of Science:
- Cardiovascular Health
- Primary Care Quality Improvement
- Health Services Research
Background:
- The Healthy Hearts in the Heartland (H3) study is part of the nationwide EvidenceNOW initiative.
- It focuses on improving cardiovascular health quality measures (ABCS: Aspirin, Blood Pressure, Cholesterol, Smoking cessation) in small primary care practices.
- The study assesses the feasibility of implementing Point-of-Care (POC) or POC plus Population Management (POC+PM) strategies.
Purpose of the Study:
- To evaluate the feasibility and effectiveness of two quality improvement strategies (POC and POC+PM) in primary care settings.
- To improve the "ABCS" clinical quality measures related to cardiovascular health.
- To describe the design and randomization process of the H3 study.
Main Methods:
- A practice-randomized comparative effectiveness study involving 226 primary care practices.
- Two arms: 1:1 randomization to POC or POC+PM.
- A modified constrained randomization algorithm was used to balance nine baseline variables, including ABCS measures.
Main Results:
- 112 practices were randomized to POC and 114 to POC+PM.
- Randomization achieved baseline comparability across key variables.
- Initial estimates showed similar median proportions for ABCS measures between the two arms.
Conclusions:
- The study's unique randomization approach, using surrogate baseline estimates, effectively balanced key outcomes.
- This design may be adaptable for similar practice- or cluster-randomized trials.
- Final 12- and 18-month outcome analyses are forthcoming.
Background:
The Healthy Hearts in the Heartland (H3) study is part of a nationwide effort, EvidenceNOW, seeking to better understand the ability of small primary care practices to improve "ABCS" clinical quality measures: appropriate Aspirin therapy, Blood pressure control, Cholesterol management, and Smoking cessation. H3 aimed to assess feasibility of implementing Point-of-Care (POC) or POC plus Population Management (POC + PM) quality improvement (QI) strategies to improve ABCS at practices in Illinois, Indiana, and Wisconsin. We describe the design and randomization of the H3 study.
Methods:
We conducted a two-arm (1:1, POC:POC + PM), practice-randomized, comparative effectiveness study in 226 primary care practices across four "waves" of randomization with a 12-month intervention period, followed by a six-month sustainability period. Randomization controlled imbalance in nine baseline variables through a modified constrained algorithm. Among others, we used initial, unverified estimates of baseline ABCS values.
Results:
We randomized 112 and 114 practices to POC and POC + PM arms, respectively. Randomization ensured baseline comparability for all nine key variables, including the ABCS measures indicating proportion of patients at the practice level meeting each quality measure. Median(Inner Quartile Range) values were A: 0.78(0.66-0.86) in POC arm vs. 0.77(0.63-0.86) in POC + PM arm, B: 0.64(0.53-0.73) vs. 0.64(0.53-0.75), C: 0.78(0.63-0.86) vs. 0.75(0.64-0.81), S: 0.80(0.65-0.81) vs. 0.79(0.61-0.91).
Discussion:
Surrogate estimates for the true ABCS at baseline coupled with the unique randomization logic achieved adequate baseline balance on these outcomes. Similar practice- or cluster-randomized trials may consider adaptations of this design. Final analyses on 12- and 18-month ABCS outcomes for the H3 study are forthcoming.
Trial Registration:
This trial is registered on ClinicalTrials.gov (Initial post: 11/05/2015; identifier: NCT02598284; https://clinicaltrials.gov/ct2/show/NCT02598284?term=NCT02598284&rank=1).
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