PHLT 8060 Week 4 Four-Line Boundary Memo Example

Boundary Memo: Four Lines Drawn Around the Hepatitis B Birth Dose Problem, Each Defended Against the Line Not Chosen

Student Name

Walden University

PHLT 8060: Dissertation Seminar I

Instructor Name

Month Day, Year

Boundary Memo: Four Lines Drawn Around the Hepatitis B Birth Dose Problem, Each Defended Against the Line Not Chosen

Purpose

The topic memo laid out every population, place, period and measure the birth dose worry could involve, and the evidence scan showed which parts existing sources can and cannot address. This memo draws four lines around the problem: who is included, where, over what period and by what measure. Each line is defended in its own section against the most plausible alternative, so that a committee member who would have drawn it differently can see the trade-off. A problem counts as bounded, in the account of Creswell and Creswell (2018), once its population, setting and scope are specific enough to steer data collection; these four lines are meant to meet that test.

Line 1: The Group

The problem concerns medically stable infants weighing 2,000 grams or more at birth who were not admitted to a neonatal intensive care unit. National guidance recommends the birth dose within 24 hours for medically stable infants of at least this weight, and sets different timing for lighter infants born to mothers without hepatitis B infection (Schillie et al., 2018). Including all newborns would mix infants for whom a delay is recommended with infants for whom it is not, so a lower coverage figure might reflect appropriate practice rather than a gap.

The alternative not chosen was to restrict the group to infants whose mothers' hepatitis B surface antigen status was unknown at delivery, the infants for whom the birth dose matters most. That group is the clinical heart of the problem, but in nine small hospitals it would number only a few dozen infants a year, too few to estimate coverage with useful precision, and maternal status is inconsistently recorded on birth certificates. The chosen group sacrifices clinical focus for a population large enough to study and a definition the records can support.

Line 2: The Place

The problem concerns births at the nine birthing hospitals located in the state's six most rural counties, identified by hospital of birth. The state's annual report counts births by mother's county of residence, which places rural mothers who deliver at urban hospitals in the rural figures and leaves out urban mothers who deliver at rural hospitals. Because the concern is about what rural hospitals do, counting by hospital of birth matches the problem to the place where the dose is or is not given.

The alternative not chosen was a statewide study of all birthing hospitals, comparing rural and urban facilities. It would add contrast but would multiply the data work and shift the problem from rural practice to urban-rural difference, a related but separate question.

Line 3: The Period

The problem covers births in the 30 months before the state's July 2021 change, when hospitals began buying newborn hepatitis B vaccine themselves, and the 30 months after, from January 2019 through December 2023. Equal periods on either side allow a comparison that does not depend on one unusual year, and starting in 2019 keeps most of the pre-period free of the pandemic's disruptions to hospital staffing, though not all of it.

The alternative not chosen was a single-year comparison, 2020 against 2022, which would be simpler but would place the comparison in two years distorted by the pandemic in different ways. A longer series reaching back to 2015 was also considered and set aside, because registry reporting from small hospitals was less complete before 2018, a limitation the program's staff confirmed.

Line 4: The Measure

The problem is measured as the proportion of infants in the group whose registry entry shows a hepatitis B vaccination dated the day they were born or the day after. Using the registry's dose dates, rather than the state report's summary, allows a consistent definition across the period despite the report's 2022 definition change. The two-day window approximates the 24-hour recommendation given that registry records hold dates rather than times.

The alternative not chosen was "any dose before hospital discharge," which would better capture practice for infants with longer stays but requires discharge dates that the registry does not hold and birth certificates record inconsistently. A broader measure, any dose within the first month, was rejected because it would count catch-up doses given at clinics and hide the hospital-level gap the problem is about.

What the Four Lines Leave Out

The boundaries leave out infants born at birthing centers and at home, who fall outside hospital practice and are inconsistently linked in registry data; preterm infants under 2,000 grams; the question of why doses are missed, whether omission, refusal or recording failure; and any outcome beyond the dose itself, such as perinatal infections. Each exclusion is a candidate for a later study, and naming them now prevents the problem statement from implying more than the bounded study can show (Booth et al., 2016).

The Problem as Bounded

Taken together, the lines produce this working statement: for clinically well newborns of 2,000 grams and up delivered at the region's nine hospitals over the five calendar years 2019 to 2023, the proportion with a hepatitis B birth dose recorded on the date of birth or the following day, and whether it differed after hospitals began purchasing newborn vaccine in July 2021, is not known. The statement will be tested against classmates' critiques and refined further before it becomes a research question.

References

Booth, W. C., Colomb, G. G., Williams, J. M., Bizup, J., & FitzGerald, W. T. (2016). The craft of research (4th ed.). University of Chicago Press.

Creswell, J. W., & Creswell, J. D. (2018). Research design: Qualitative, quantitative, and mixed methods approaches (5th ed.). SAGE.

Schillie, S., Vellozzi, C., Reingold, A., Harris, A., Haber, P., Ward, J. W., & Nelson, N. P. (2018). Prevention of hepatitis B virus infection in the United States: Recommendations of the Advisory Committee on Immunization Practices. MMWR Recommendations and Reports, 67(1), 1-31. https://doi.org/10.15585/mmwr.rr6701a1