Introduction
Quantitative research deals with measuring associations between variables. The aim of quantitative research is to establish the association between dependent and independent variables in a population. Identifying an appropriate population sample size and ensuring randomization of the sample selection are key steps of a quantitative researcher. This paper will analyze how a sampling strategy can strengthen or weaken a quantitative research study. It will critique the sampling strategy and sample size in a quantitative research study article known as “The Efficacy of Female Condom Skills Training in HIV Risk Reduction among Women: A Randomized Controlled Trial by researchers at the University of California in San Francisco”. This study hypothesized that if women were trained about how to use the female condom, its efficacy would increase along with its usage. When critiquing a chosen article’s sampling technique and size, one needs to scrutinize the study population (Choi et al, 2008).
Critiquing Sampling Strategy and Sample Size in the Article Sampling Strategy
When conducting research, it is impossible and expensive to test everyone for a variable. Some variables only exist in certain populations. Researchers have to sample a population or group of individuals to determine which group, population, or ethnic group contains variables such as certain genetic markers that would respond to medication. Some variables are broad and can include a fantastic deal of individuals. Others might seek to obtain information from a smaller portion of the population called a sample. Quantitative researchers should work with a sample of the populace and not the entire population. The best way of making certain that it is representative is by using a random selection process. The sample can represent the population as a whole. The process for choosing the appropriate sample is called sampling (Gerstman, 2008).
Sampling technique is used to represent a group of individuals in a population, since it would be impossible to test the entire population. This method creates generalization about the population being studied. Sampling can be conducted when program funding is limited and can only support a small number of participants. Sampling of a smaller portion of the population can sometimes yield a higher quality of data since other variables are kept to a minimum (Singleton & Straits, 2005).
The study population in the above mentioned research article was non-diverse with a population of 64% of the participants being white. The largest age group in this sample was women aged 20-24. 91% of the population was not married, and the majority had education levels lower than high school. Many of the participants had one sexual partner (Choi et al, 2008). The researchers in this study were unable to obtain a consistent and equally represented population. This meant that the sampling technique was not appropriate (Friis & Sellers, 2004).
Sample size
The question of how many subjects should be studied is extremely beneficial in a quantitative study. Determination of sample size is highly crucial in quantitative research. The sample size used in this article can be critiqued. At the end of the study, the sample size was vastly different from the initial sampling size at the beginning of the study. The research study started with a total of 756 participants and this reduced to 409 (Singleton & Straits, 2005).
The article, however, stated reasons for the reduction in sample size. Factors such as participant’s lack of attendance, failure to complete all study visits and adhesion to study requirements caused researchers to have their study population reduced. Further factors that affected the sampling technique were the recruiting techniques developed by the study’s researchers (Choi et al, 2008).
Participants in this study were obtained only from three family planning clinics, and only women who responded to a posted advertisement were recruited. The sampling population was restricted and did not represent a larger population of women. These factors along with the non-diversification of the population showed a lack of proper sampling by study researchers (Choi et al, 2008). The following should be done so as to strengthen the researcher’s sampling technique. The researcher has to increase the study population, include women outside the clinic, and standardize population variables such as age, marital status, race and ethnicity.
References
Choi, K., Hoff, C., Gregorich, S, E., Grinstead, O., Gomez, C., & Hussey, W. (2008).
The efficacy of female condom skills training in HIV risk reduction among women: A randomized controlled trial. A Journal of Public Health, 98(10), 1841-1847.
Friis, R.H. & Sellers, T.A. (2004). Epidemiology for public health practice. 3rd edition. Sudbury, Mass: Jones and Bartlett.
Gerstman, B.B. (2008). Basic biostatistics: statistics for public health practice. Sudbury, MA: Jones and Bartlett.
Singleton, R.A. and Straits, B.C., (2005). Approaches to social research: 4th edition. New York: Oxford University Press.