How to Establish and Follow up a Large Prospective Cohort Study in the 21st Century--Lessons from UK COSMOS.

Large-scale prospective cohort studies are invaluable in epidemiology, but they are increasingly difficult and costly to establish and follow-up. More efficient methods for recruitment, data collection and follow-up are essential if such studies are to remain feasible with limited public and research funds. Here, we discuss how these challenges were addressed in the UK COSMOS cohort study where fixed budget and limited time frame necessitated new approaches to consent and recruitment between 2009-2012. Web-based e-consent and data collection should be considered in large scale observational studies, as they offer a streamlined experience which benefits both participants and researchers and save costs. Commercial providers of register and marketing data, smartphones, apps, email, social media, and the internet offer innovative possibilities for identifying, recruiting and following up cohorts. Using examples from UK COSMOS, this article sets out the dos and don'ts for today's cohort studies and provides a guide on how best to take advantage of new technologies and innovative methods to simplify logistics and minimise costs. Thus a more streamlined experience to the benefit of both research participants and researchers becomes achievable.

Improving the success rate of gluteal intramuscular injections.

OBJECTIVES: This study aimed to improve the success rate of gluteal intramuscular (IM) injection. METHODS: The outcomes of 328 intended gluteal IM injections in 115 patients receiving depot octreotide were evaluated using computed tomography performed in routine clinical practice. Patient-, nursing-, and technique-dependent factors were correlated with successful delivery of medication. Techniques associated with successful injection were taught to center nurses. RESULTS: At baseline, 52% of injections were successfully delivered (66% men, 36% women; P = 0.001). Factors associated with successful delivery included nurses' frequency of injections (P = 0.008), landmarks use to select injection site (P < 0.001), quick needle insertion (P < 0.001), and use of nonsyringe hand to compress injection site (P < 0.001). Patient-related factors included male sex (P < 0.001), lower body mass index (P < 0.001), and lower skin-to-muscle depth at injection site (P < 0.001). Techniques associated with successful injections were then taught to center nurses. After instruction, the success rate increased from 52% to 75% (P = 0.001). Importantly, improvements were observed in both men (66%-75%; P = 0.43) and women (38%-75%; P < 0.001). Successful injection was associated with better control of flushing among those with carcinoid syndrome (P = 0.005). CONCLUSIONS: Intended gluteal IM injections often are given into the subcutaneous space. Education in techniques associated with successful injections improves IM delivery rates.