The RCT will be conducted to test the screening intervention, the Cardiovascular Assessment Screening Program, with nurse practitioners across NL.
Research Questions
1. What is the effect of implementing the Cardiovascular Assessment Screening Program on comprehensiveness of screening by nurse practitioners in NL?
2. What is the effect of implementation of the Cardiovascular Assessment Screening Program on the identification of individuals at high risk of CVD within the nurse practitioner practice?
3. What is the effect of implementation of the Cardiovascular Assessment Screening Program on recommendations that are made by nurse practitioners in NL?
4. What components of the Cardiovascular Assessment Screening Program are effective in promoting CVD screening and appropriate follow-up by nurse practitioners in NL?
5. What are the patients' and nurse practitioners' factors that influence participation in the Cardiovascular Assessment Screening Program in NL? The main outcome is the comprehensiveness of CVD screening. The null hypothesis for the RCT is stated as follows: There will be no difference in comprehensiveness of screening between the intervention group and the control group.
Methodology The RCT study will involve implementation and evaluation of the Cardiovascular Assessment Screening Program across the province of NL. The RCT will use block randomization following NP recruitment to allocate participating NP practices to either the intervention group or the control group. The NPs in the intervention group will participate in scheduled face-to-face educational sessions as well as webinars from their workplaces to receive support on using specific tools to identify, screen, and follow-up with patients. The NPs will also receive instructions on data collection methods using the study's Access Database developed by Newfoundland and Labrador Centre for Health Information (NLCHI).
The NPs in the control group will participate in a webinar education session and will be instructed to follow usual practice to screen patients for CVD. The NPs in the control group will receive instructions on keeping a record of patients who were seen in their clinics and whether or not the patients will be eligible to participate in the study based on age and history. This information will be used by researchers to conduct a retrospective chart review on a specified date during the data collection period. The specific CVD screening tools provided to the NPs in the intervention group will be made available to NPs in the control group following conclusion of this study.
Setting \& Sample The RCT will take place in community-based clinics with NP practices from both rural and urban areas in the various regional health authorities across NL. NPs may be working in solo practice or working with several other NPs in a group practice. There will be four types of NP practices: 1) rural solo, 2) rural group, 3) urban solo and, 4) urban group. NPs working in the same group practice will need to be allocated to the same group, so block randomization will be used once all of the NP practices have been recruited. Using a random number generator, NP practices will be allocated to either the intervention group or the control group within each block (type) of practice.
The sample size estimation for this study was determined using the proportion of eligible patients who were comprehensively screened as the outcome measure of interest. A study that considered the effectiveness of a national risk assessment program for patients aged 40-74 years found that approximately 40% had complete Health Checks and 60% had partial Health Checks among high risk patients in the United Kingdom (UK) National Health Service Health Check Program (Artec et al., 2013). The sample size for this proposed study was calculated based on the assumption that 40% of the screening will be comprehensive in the control group practices. The research team decided that comprehensive screening of 70% of patients seen by the NPs in the intervention group during this study would indicate an effective intervention. Using a two-sided alpha of 0.05 and 90% power, the sample size was calculated to be 250 patients (125 patients per group). Considering that patients would need to provide consent to participate in this study the research team assumed that 20% of those approached would refuse. This means that 300 patients with 150 patients per group would be required. To be realistic about workload, each NP would need to include 25-30 patients. A minimum of 10 NPs therefore needs to be recruited. The duration of the data collection period will vary by NP according to the number of eligible patients seen. For example, if an NP sees one eligible patient per day for five days a week, then the data collection period would be six weeks for a total of 30 patients. If an NP sees two eligible patients per day, then the data collection period would be three weeks.
