Chapter 3: Methods for Evaluating a Community Health Worker Hypertension Program
Student Name
Doctor of Public Health Program, Aspen University
DPH 860: Advanced Biostatistics
Instructor Name
Month Day, Year
Chapter 3: Methods for Evaluating a Community Health Worker Hypertension Program
Chapter 3 of a doctoral project manuscript explains how the study was conducted in enough detail for another researcher to repeat it and for readers to judge its validity. This paper drafts Chapter 3 for a capstone that evaluates a community health worker service for residents with hypertension in a composite county's east-side neighborhoods.
Purpose of the Chapter
The chapter describes the design, setting, participants, intervention, variables, data sources, sample size, statistical analysis and ethical safeguards. It connects the research questions from Chapter 1 and the evidence gaps from Chapter 2 to the results that will be presented in Chapter 4.
Chapter Structure
The table outlines the chapter's sections and required content.
| Section | Must contain |
|---|---|
| Design | Matched comparison design and rationale |
| Setting | County, clinics, time period |
| Participants | Eligibility, enrollment, matching |
| Intervention | Program components, dose, staff |
| Variables | Outcomes, exposure, covariates, definitions |
| Data sources | Clinical records, program data, linkage |
| Sample size | Power calculation and assumptions |
| Analysis | Models, missing data, sensitivity, subgroups |
| Ethics | Review board determination, privacy |
Design
The study uses a retrospective matched comparison design. Program participants are compared with adults from the same clinics who did not enroll, matched by propensity score. This design was chosen because randomization was not feasible once the program was running, and matching reduces confounding by measured characteristics (Austin, 2011).
Setting and Participants
The setting is three east-side neighborhoods of a composite county of 420,000, served by a hospital system and two community health centers. Eligible adults were aged 18 to 85 with a systolic pressure of 140 mmHg or higher at two visits in the year before enrollment. Seven hundred participants enrolled between January 2024 and June 2025 and were matched one to one with 700 comparison adults.
The Intervention
Eight community health workers from the neighborhoods provided home visits, blood pressure monitors, medication support, help with appointments and pharmacy access and referrals for social needs. Participants received a median of nine visits over 12 months. Workers were supervised by a nurse and trained in motivational interviewing and home blood pressure measurement.
Variables and Measures
The primary outcome is blood pressure controlled below 140/90 at the visit closest to 12 months after enrollment. The secondary outcome is change in systolic pressure. Adjustment variables cover demographic characteristics, insurance, diabetes, the number of medications and neighborhood. All variables are defined in the codebook, provided as an appendix.
Data Sources
Clinical data come from the hospital system and health centers' electronic records under data use agreements. Program data come from the health department's enrollment and visit records. Records were linked by a trusted third party using name, date of birth and address and then de-identified. The linkage match rate and characteristics of unlinked records are reported in the flow diagram.
Sample Size
With 700 per group, power exceeds 80% for the smallest effects judged meaningful, 10 points in control and 4 mmHg in systolic change, with two-sided alpha of 0.05, allowing for 15% missing outcomes. Calculations were checked with G*Power (Faul et al., 2007).
Statistical Analysis
Balance after matching is assessed with standardized differences. Conditional logistic regression estimates the effect on control, and a linear mixed model estimates the effect on systolic change, adjusted for baseline pressure. Missing outcomes are handled by multiple imputation, with complete-case and alternative matching analyses as sensitivity checks.
Ethics
The institutional review board determined that the project is a program evaluation using de-identified data with minimal risk. Data sit on encrypted servers, and only grouped results are published. The health department and clinics approved data use. Clinic staff were informed that the evaluation assesses the program, not individual performance.
Reporting Standards
The chapter follows STROBE recommendations for reporting observational studies, including a participant flow diagram and a description of how bias and missing data were addressed (von Elm et al., 2007).
Limitations of the Method
Matching addresses only measured confounders; participants may differ from comparison adults in motivation or social support. Blood pressure readings from routine visits vary in technique. Results apply to the county's east side and may not generalize to other settings.
Research Questions Restated
The chapter restates the research questions from Chapter 1. First, does program participation increase the proportion of adults with controlled blood pressure at 12 months compared with matched nonparticipants? Second, does participation produce a greater reduction in systolic pressure? Third, do effects differ by age, sex, insurance or baseline pressure?
Measurement Quality
Blood pressure readings come from routine clinic visits using automated devices. Clinics follow a standard protocol requiring rest before measurement, though adherence varies. The chapter describes the protocol, notes that measurement error would likely bias results toward no difference and reports a sensitivity analysis limited to clinics with documented protocol training.
Fidelity of the Intervention
Program fidelity was tracked through visit logs, supervisor reviews and a checklist of core activities. Participants received at least one home blood pressure monitor and medication review in 94% of cases. Reporting fidelity helps readers understand what the program actually delivered.
Transition to Chapter 4
The chapter ends by explaining how results in Chapter 4 will follow the same order: participant flow, baseline characteristics and balance, primary and secondary outcomes, sensitivity analyses and subgroup analyses. Consistent structure makes the manuscript easier for the committee to review.
Writing Style
Methods chapters are written in the past tense for completed steps and describe procedures precisely, avoiding interpretation. Tables and the appended codebook carry detail that would clutter the text, allowing the chapter to remain readable while complete.
Timeline of Data Collection
Enrollment ran from January 2024 to June 2025, and 12-month outcome data were collected through June 2026. Data extraction occurred in July and August 2026 after all data use agreements were signed. Reporting these dates allows readers to understand the time frame and any secular changes, such as new hypertension medications, that might affect results.
Researcher Role
The author was placed with the health department during the evaluation but was not involved in delivering the program. This separation reduces the risk that the evaluator's expectations influenced program delivery, and the chapter states it explicitly as part of describing potential sources of bias.
Conclusion
Chapter 3 describes a matched comparison design, setting, participants, intervention, variables, data sources, sample size, analysis and ethics in sufficient detail to allow replication and appraisal. It prepares the ground for Chapter 4, where results will be reported following the same structure.
References
Austin, P. C. (2011). An introduction to propensity score methods for reducing the effects of confounding in observational studies. Multivariate Behavioral Research, 46(3), 399-424. https://doi.org/10.1080/00273171.2011.568786
Faul, F., Erdfelder, E., Lang, A.-G., & Buchner, A. (2007). G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior Research Methods, 39(2), 175-191. https://doi.org/10.3758/BF03193146
von Elm, E., Altman, D. G., Egger, M., Pocock, S. J., Gøtzsche, P. C., & Vandenbroucke, J. P. (2007). The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: Guidelines for reporting observational studies. The Lancet, 370(9596), 1453-1457. https://doi.org/10.1016/S0140-6736(07)61602-X
How this DPH 860 Module 8 example is structured
Check the DPH 860 prompt in your Aspen classroom before using this example. It explains the chapter's purpose, tables its sections, then describes design, setting, intervention, variables, data sources, sample size, analysis, ethics, reporting standards and limitations.
DPH 860 Module 8 questions, answered
What does DPH 860 Module 8 usually ask for?
Aspen's DPH 860 includes Chapter 3 of the project, so drafting the methods chapter is a typical final assignment. Follow your classroom prompt.
What belongs in a methods chapter?
Design, setting, participants, intervention, variables, data sources, sample size, analysis, missing data, ethics and limitations.
How detailed should Chapter 3 be?
Detailed enough that another researcher could repeat the study and readers could judge its validity.
Write yours, or have the desk draft it
This paper is an original model document written by our desk, not a submitted student paper and not an official Aspen University document. Read it for the moves, then write your own to the instructions in your classroom. If you want one built to your exact prompt and rubric, the first custom sample is free and arrives in 24 to 48 hours.