A mapping review of worldwide current and previous cohort research programmes in cats and dogs

Abstract

Cohort research programmes follow individuals over time to enable study of effects from various factors on health or other outcomes. To date, the global distribution of formal cohort programmes in cats and dogs has not been mapped, and a comprehensive synthesis of their methodological characteristics is lacking. That limits methods improvement and wider adoption of cohort programmes in veterinary medicine. A mapping review methodology aligned with the JBI Manual for Evidence Synthesis was used to summarise existing cohort research programmes on cats and dogs worldwide. Electronic databases were searched (Embase, MEDLINE, Scopus, Web of Science) to identify eligible cohort papers, followed by a two-step selection process (title and abstract screening, full text screening) for paper inclusion. Information extracted at the individual cohort programme level covered: 1. location and veterinary specialty; 2. study design; 3. study variables; 4. collected data; 5. recruitment and retention strategies. Database searches yielded 6,777 unique papers, of which 73 met the inclusion criteria. Twenty-two programmes were identified, predominantly in the UK (8/22, 36%) or US (6/22, 27%) with 55% (12/22) involving dogs. Most of the programmes (18/22, 82%) aimed at disease prevention. Out of 19 programmes for which full-text papers were available, and therefore more information could be extracted, animal demographics were the most commonly considered study variable (15/19, 79%). The biggest reporting gaps were identified in the study planning phase, design, and programme management. Consequently, limited information was retrievable from the programmes papers to create learning opportunities for other researchers planning future cohort programmes. Improved or new reporting practices are needed to enhance knowledge sharing and promote cohort programmes in veterinary medicine. The study protocol was preregistered on the 27th of December 2023 (https://osf.io/wkg53/).

Fig 1. PRISMA flow diagram of records selection for the cats and dogs research cohort programmes mapping review.

Fig 2. Map illustrating the global distribution of the cats and dogs cohort research programmes selected for the mapping review, with the shades indicating the number of programmes per country.

Reprinted from www.mapchart.net under a CC BY 4.0 license, with permission from the owner and developer of MapChart.

Fig 3. Bar plot with the bar width representing the number of cats and dogs cohort research programmes, selected for the mapping review, in each veterinary research specialties.

Fig 4. Groups of study variables, considered in the selected cats and dogs cohort research programmes.

Bar plot illustrating the collected information on considered groups of study variables, indicated in yellow the number of programmes for which there was evidence that they were included and in orange the number of programmes for which they were not included. We could not determine whether study variables were used in some programmes. Therefore, the height of the bars does not correspond to 19, but to the total number of programmes for which information about study variables could be extracted.

Fig 5. Promotion methods used to encourage recruitment in the 19 cats and dogs research cohort programmes selected for the mapping review.

*Mainstream media includes newspapers, television, radio, and magazines. **KC- Kennel Club. ***Posters training- posters displayed at dog training locations.

Fig 6. Box plot representing planned target sample or the largest reported number of recruited animals and funding structure in the cats and dogs research cohort programmes selected for the mapping review.