Coronary Heart Disease, Research Paper Example

Critique of Quantitative Research Methods: Understanding How Nurse Practitioners Estimate Patients’ Risk for Coronary Heart Disease

Nurse practitioners play a vital role in various medical settings. One important role that nurse practitioners play is estimating a patient’s risk for contracting a disease. Coronary heart disease has become one of the most common diseases in the developed world (Beckstead & Stamp 2007). Cardiovascular disease is the cause for half of the deaths in the developed world (World Health Organization 2002). Because many nurse practitioners are now working side by side with primary care physicians, the need for them to understand and estimate a patient’s disease risk is crucial. Jason Beckstead and Kelly Stamp create a study to determine how well-equipped nurse practitioners are for engaging in the tasks of early prevention and disease detection.The following is an analysis of the article Understanding How Nurse Practitioners Estimate Patients’ Risk for Coronary Heart Disease.

Problem or Purpose

The main purpose of the study was to examine how nurse practitioners combine information when estimating a patient’s risk of CHD (Beckstead & Stamp 2007). Because coronary problems have become so common, it is vital for nurses to be able to identify the signs and symptoms early on. The secondary purpose of this study was to determine the most common methods used by nurse practitioners to determine whether or not a patient is at risk for CHD.

Literature Review

The main article is an attempt to identify how nurse practitioners detect CHD. The other three scholarly articles include related studies and information. The article Positive non-invasive tests in the chest pain unit: importance of the clinical profile for estimating the probability of coronary artery disease is a study that investigates non-invasive methods for determining if CHD is the cause of chest pain in patients (Martínez-Sellés et al 2008). The article Prediction of risk of death and myocardial infarction in the six months after presentation with acute coronary syndrome: prospective multinational observational study evaluates whether or not there is a link between CHD and myocardial infarction as well as morbidity (Fox et al 2006). The article Estimating the Relative Risk in Cohort Studies and Clinical Trials of Common Outcomes examines the study of common outcomes (McNutt et al 2003).

Theoretical and Conceptual Framework

The theoretical and conceptual frameworks used in the article were situational judgment tests (SJT). This type of framework is typically used to analyze subjects’ response to workplace situations. Written tests are the most common form of SJT. The nurse practitioners were given booklets with hypothetical scenarios and were instructed to record their responses.

Research Questions

The study is based upon five separate, yet related research questions which are explicitly stated in the beginning of the article. These questions are:

“1) How do individual NPs distribute importance weights among cues as they estimate risk?

2) How accurate are their estimates when compared with a ‘gold-standard’ prediction rule?

3) How well does the additive linear model capture NPs’ judgment policies?

4) How much agreement is there among NPs as they estimate risk?

5) How much self-insight do NPs have into their risk estimation processes?” (Beckstead & Stamp 2007)

 Major Study Variables

The independent variables of this study included the written tests that the nurses were assigned. The dependent variable is the responses received on the test from the nurses. The demographic variables of the study include nurse practitioners from West-central Florida in the United States. Male and female participants were involved. Operational variables include the nurses themselves.

 Research Design

The research design was a correlational study. A correlational study investigates the relationships among variables. In the case of this particular study, the researchers were investigating the correlation between the dependent variable (the responses on the written test) and the operational variable (the nurses).

 Sample and Setting

“The volunteer judges used in the study were a convenience sample of 15 NPs practicing in west-central Florida, USA. They were recruited through word of mouth. Two were male. NPs ranged in age from 34 to 55 years, with an average of 46.1. The majority (66.6%) worked in primary care settings. The judges had, on average, 10.1 years of experience practicing as NPs (range 3–23). The study was approved by the university’s institutional review board for research. Participants were assured of anonymity and confidentiality” (Beckstead & Stamp 2007).

Measurement Instrument

“Materials were presented to the judges in booklets. Booklets contained a cover page describing the purpose of the study, instructions for the PC task, a series of patient profiles, a section asking judges to indicate how they assigned importance to the cues during the PC task, and a section requesting demographic information. These sections are described below. A certain ratio was achieved by the study participants” (Beckstead & Stamp 2007).  The entire procedure took approximately thirty-two minutes (Beckstead & Stamp 2007).

Data Collection

“Judges were tested individually and in small groups in office and classroom settings. After obtaining informed consent, instructions were read aloud to the judges. The procedure took an average of 32 minutes (range 20–47) to complete. Data collection took place in 2006” (Beckstead & Stamp 2007).

Statistical Analysis

“Data were analyzed to address the research questions raised above. We present our results below in sections corresponding to these questions. Regression analyses were conducted separately for each NP using SPSS version 15. Prior to aggregating any correlation coefficients (ra, Rs, G, and test retest r) Fisher’s Z transformation was applied; aggregated values were then transformed back to original metric for presentation. Before considering questions of accuracy, cue weighting strategies, and self-insight, we address the quality of our data” (Beckstead & Stamp 2007).

“Consistency was measured for each NP by calculating the correlation of responses made to the 10 duplicate cases with those made to their counterparts in the set of 70 cases. The mean of this test-retest correlation was 0.838, indicating sufficient although non-uniform performance. Judges indicated that the patient profiles were realistic Mean = 7.8, SD = 2.26, offering support for the face validity of the judgment task” (Beckstead & Stamp 2007).

Research Results and Findings

The judges in the study had widely varying levels of accuracy in their determination of a possibility for CHD. There were two indexes of accuracies that were used in this study. The first was the use of LME. For this test, “judge 7 had the highest value while judge 15 had the lowest” (Beckstead & Stamp 2007). The second accuracy index that was used was root mean square error or RMSE (Beckstead & Stamp 2007). For this test, “judge 9 was the most accurate while judge 11 was the least accurate” (Beckstead & Stamp 2007).

Nurses are required to have a certain level of self-insight into the risk estimation process. Determining the level of self-insight for each nurse consisted of using another research method. “Nurse practitioners’ insight into their own judgment policies was analysed by replacing regression coefficients with self-reported cue weights in the regression equation and computing risk for the profiles” (Beckstead & Stamp 2007).

Replication of the Study

The description of the study is not specifically clear to replication. One can logically infer, however, that this particular study can be replicated as the variables that are involved in the study are fairly simple to replicate.

Discussion

The first thing that the researchers list in the discussion section is the limitations of the study. The pencil and paper patient profiles presented to the participants were quite brief (Beckstead & Stamp 2007). Geographic limitations also apply to this study as the group consisted of a small convenience sample located in Western Florida, therefore their views and abilities may differ from nurses in other states or even in other countries (Beckstead & Stamp 2007). The researchers compare their information to previous studies. “The PC method employed was successful in adequately modeling the NPs estimates of patient risk for CHD” (Beckstead & Stamp 2007). Because many of the NPs had lower values on environmental knowledge than on cognitive control, educational institutions should focus upon working with students to build these skills (Beckstead & Stamp 2007).

References

Beckstead, J., & Stamp, K. (2007). Understanding how nurse practitioners estimate patients’ risk for coronary heart disease: a judgment analysis. Journal of Advanced Nursing, 60(4), 436-446. doi:10.1111/j.1365-2648.2007.04406.x.

Fox, K. A., Granger, C. B., Anderson Jr., F. A., Dabbous, O. H., Goldberg, R. J., Pieper, .S., et al. (2006). Prediction of risk of death and myocardial infarction in the six months after presentation with acute coronary syndrome: prospective multinational observational study (GRACE). BMJ, 333, 1091-1094.

Martínez-Sellés, M., Bueno, H., Estévez, Á., De Miguel, J., Muñoz, J., & Fernández-Avilés, F. (2008). Positive non-invasive tests in the chest pain unit: importance of the clinical profile for estimating the probability of coronary artery disease. Acute Cardiac Care, 10(4), 205-208. doi: 10.1080/17482940701805408.

McNutt, L., Wu, C., Xue, X., & Hafner, J. P. (2003). Estimating the Relative Risk in Cohort Studies and Clinical Trials of Common Outcomes. American Journal of Epidemiology,157(10), 940-943.