DNP 800 Module 5 assignment: documented search strategy, a full sample

Finding the Evidence on Keeping Older Inpatients Moving: A Documented, Reproducible Literature Search Strategy

Student Name

Doctor of Nursing Practice Program, Aspen University

DNP 800: Theoretical and Scientific Underpinnings

Instructor Name

Month Day, Year

Finding the Evidence on Keeping Older Inpatients Moving: A Documented, Reproducible Literature Search Strategy

A literature review is only as good as the search behind it. A search that cannot be repeated, or that misses important studies, produces a review that cannot be trusted. This paper documents the search strategy for the review of literature on a doctoral practice topic: whether structured mobility and exercise programs during hospitalization prevent functional decline in older adults. It defines the question, breaks it into concepts, lists the subject headings and keywords used in each database, explains the limits, describes how results will be screened and recorded, and reflects on the search's weaknesses.

The Question

The review question, framed with the PICO elements, is: among adults aged 65 and older hospitalized on acute medical units (P), do structured mobility or exercise programs delivered during the stay (I), compared with usual care (C), reduce loss of independence in activities of daily living, and affect length of stay and discharge destination (O)? Stating the outcomes explicitly matters, because some studies of hospital mobility measure steps or time out of bed rather than function, and those studies answer a different question.

Starting Point

Before searching broadly, the student looked for existing systematic reviews, since a good review saves time and shows which terms other researchers used. A Cochrane review of exercise for acutely hospitalized older medical patients screened 3,138 articles and included seven randomized and two controlled clinical trials. It found the effect of exercise alone on functional outcomes unclear, but pooled analyses of multidisciplinary interventions that included exercise showed a small increase in discharge home and reductions in length of stay and cost (de Morton et al., 2007). Because that review is now old, the new search is designed to find trials published since, including large trials such as one in which daily individualized exercise reversed functional decline in adults aged 75 and older (Martínez-Velilla et al., 2019).

Concepts and Terms

The question contains three core concepts: older adults, hospitalization and mobility or exercise. Outcomes are not searched as a concept, because doing so risks missing studies that report function among many outcomes; instead, outcomes are applied at screening. For each concept, the search combines controlled vocabulary with keywords, joined within a concept by OR and across concepts by AND.

In PubMed, the combined search is written as the three concept blocks joined with AND, with each block containing its subject headings tagged as MeSH terms and its keywords tagged to title and abstract. In CINAHL, the same structure uses CINAHL headings with the explode option where appropriate. The Cochrane Library is searched with keywords only, and the physiotherapy evidence database is searched for trials with the simple terms hospital, older and exercise. The bibliographies of included trials and of the Cochrane review are checked by hand, and citation tracking is used for the most relevant trials.

Limits and Their Rationale

The search is limited to English-language studies because the student cannot appraise studies in other languages, a limit that is acknowledged as a possible source of bias. Dates are limited to 2006 onward, the year before the Cochrane review's publication, so that trials published after its search are captured with overlap. Study design is not limited in the search itself; instead, randomized trials, controlled trials and systematic reviews are selected at screening, because design filters can miss poorly indexed trials. Studies in intensive care or surgical units are excluded at screening, since their patients and interventions differ.

Screening and Recording

Records are exported to a reference manager, duplicates are removed, and titles and abstracts are screened against the inclusion criteria, followed by full-text review. Each step is recorded in a flow diagram in the format recommended by the PRISMA 2020 statement, including the number of records found in each database, duplicates removed, records screened and excluded, full texts assessed and reasons for exclusion (Page et al., 2021). Although a DNP literature review is not a full systematic review, following this structure makes the process transparent and repeatable. The date of each search and the exact search string are saved so the search can be rerun before the project proposal is finalized.

To keep decisions consistent, the screening criteria are fixed before screening begins. Studies are included if they enroll adults aged 65 or older, or report results for that group, on acute medical units; test a mobility, walking or exercise intervention delivered during the stay; include a comparison group; and report at least one functional outcome, length of stay or discharge destination. Protocols, conference abstracts and studies in rehabilitation units are excluded.

Weaknesses of the Strategy

The strategy has limits. Terminology in this field is inconsistent: mobility, ambulation, activity and exercise are used interchangeably, and some interventions are described as care models, such as acute care for elders units, rather than as exercise programs, so relevant studies may be missed. A single reviewer screening all records increases the chance of errors. The student will reduce these risks by testing whether the search retrieves a set of known key trials, adding terms if it does not, and asking a librarian to review the strategy.

Publication bias is another concern. Journals publish small trials with positive results more readily than small trials that find nothing, which may exaggerate apparent benefits. Searching trial registries for completed but unpublished studies partly addresses this risk, and the review will note where the evidence base appears to lean toward positive results.

Conclusion

A documented search strategy turns the literature review from a collection of articles into a reproducible process. For the question of whether in-hospital mobility and exercise programs prevent functional decline in older adults, the strategy starts from an existing Cochrane review, combines subject headings and keywords across three concepts in several databases, applies limits with stated reasons, and records every screening decision in a standard format. Its known weaknesses, especially inconsistent terminology, are addressed through testing and expert review.

References

de Morton, N. A., Keating, J. L., & Jeffs, K. (2007). Exercise for acutely hospitalised older medical patients. Cochrane Database of Systematic Reviews, 2007(1), Article CD005955. https://doi.org/10.1002/14651858.CD005955.pub2

Martínez-Velilla, N., Casas-Herrero, A., Zambom-Ferraresi, F., Sáez de Asteasu, M. L., Lucia, A., Galbete, A., García-Baztán, A., Alonso-Renedo, J., González-Glaría, B., Gonzalo-Lázaro, M., Apezteguía Iráizoz, I., Gutiérrez-Valencia, M., Rodríguez-Mañas, L., & Izquierdo, M. (2019). Effect of exercise intervention on functional decline in very elderly patients during acute hospitalization: A randomized clinical trial. JAMA Internal Medicine, 179(1), 28-36. https://doi.org/10.1001/jamainternmed.2018.4869

Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D., Shamseer, L., Tetzlaff, J. M., Akl, E. A., Brennan, S. E., Chou, R., Glanville, J., Grimshaw, J. M., Hróbjartsson, A., Lalu, M. M., Li, T., Loder, E. W., Mayo-Wilson, E., McDonald, S., . . . Moher, D. (2021). The PRISMA 2020 statement: An updated guideline for reporting systematic reviews. BMJ, 372, Article n71. https://doi.org/10.1136/bmj.n71