Sampling is a very complex issue in qualitative research as there are many variations of qualitative sampling described in the literature and much confusion and overlapping of types of sampling, particularly in the case of purposeful and theoretical sampling. A manual for selecting sampling techniques in research. Purposive sampling, is a form of nonprobability sampling in which researchers rely on their own judgment when choosing members of the population to participate in their study 20. To say one will engage in purposive sampling signifies that one sees sampling as a series of strategic choices about with whom, where, and how one does ones research. A purposive sample might gather clinicians, patients, administrators, staff, and former patients together so they can talk as a group.
It is called this due to the researcher applying their own criteria when defining their sample, so in layman terms the researcher selects their own individuals as part of their study. Nov 15, 2016 one of the more popular methods is called purposive sampling. A manual for selecting sampling techniques in research 4 preface the manual for sampling techniques used in social sciences is an effort to describe various types of sampling methodologies that are used in researches of social sciences in an easy and understandable way. Pdf purposeful sampling in qualitative research synthesis. Feb 21, 2012 scientific essay from the year 2012 in the subject business economics business management, corporate governance, language.
Jan 01, 2016 convenience sampling technique is applicable to both qualitative and quantitative studies, although it is most frequently used in quantitative studies while purposive sampling is typically used in qualitative studies 5. Purposive sampling is intentional selection of informants based on their ability to elucidate a specific theme, concept, or phenomenon. For example, we might select every nth name in a phone book, visit every 8th. Purposive sampling in a qualitative evidence synthesis. A field manual for applied research provides a very. Jan 31, 2019 in a qualitative evidence synthesis, too much data due to a large number of studies can undermine our ability to perform a thorough analysis. Sage books the ultimate social sciences digital library. In a qualitative evidence synthesis, too much data due to a large number of studies can undermine our ability to perform a thorough analysis. The main objective of purposive sampling is that the researcher, with his good decision and appropriate policy, chooses those elements which are meant for fulfilling the research objective.
This will not be achieved through superficial knowledge about a large, representative sample of individuals. In nonprobability sampling also known as nonrandom sampling not all members of the population has a chance of participating in the study. In probability sampling, each unit is drawn with known probability, yamane, p3 or has a nonzero chance of being selected in the sample. It uses the judgment of an expert in selecting cases or it selects cases with a specific purpose in mind. To draw a convenience sample, we would simply collect data from those people or other relevant elements to. Sampling and choosing cases in qualitative research. The purposive sampling technique is a type of nonprobability sampling that is most effective when one needs to study a certain cultural domain with knowledgeable experts within. Sampling and data collection in qualitative studies nurse key.
Leech university of colorado at denver, denver, colorado the purpose of this paper is to provide a typology of sampling designs for qualitative researchers. In simple random sampling each member of population is equally likely to be chosen as part of the sample. The objective of this article is to describe the development and application of a sampling framework for a qualitative evidence synthesis on vaccination communication. When enough information is known to identify characteristics that may influence how the phenonmenon is manifest, then it may make sense to use a stratified purposeful sampling approach. We have chosen a mixed purposeful sampling, combining three different strategies that we considered the most consistent with our research purpose. The use of purposeful sampling in a qualitative evidence. The chapter discusses different types of sampling methods used in qualitative research to select informationrich cases. When conducting quota sampling, a researcher identifies categories that are important to the study and. Many qualitative studies, however, evolve to a purposive or purposeful sampling strategy in which researchers deliberately choose the cases or types of cases that will best contribute to the study dozens of purposive sampling strategies have been.
Purposive sampling educational research basics by del siegle. Patton 1990 has proposed the following cases of purposive sampling. Purposive sampling generalizable or the existence of a particular kind of case will undermine all that you know to be true about a phenomenon, then look for that kind of case. While the latter two strategies may be used by quantitative. Sampling strategies in quantitative research typically involve methods that help in dealing with large amounts of data. The objective of this article is to describe the development and application of a sampling framework for a qualitative evidence.
Purposive sampling is popular in qualitative research. A study on purposive sampling method in research neetij rai bikash thapa chapter i. Stratified purposeful sampling qualitative research. Sampling data and data collection in qualitative research.
Sampling strategies for quantitative methods used in mixed methods designs in implementation research are generally wellestablished and based on probability. Pdf sampling data and data collection in qualitative research. Convenience sampling, also known as availability sampling, is a nonprobability sampling strategy that is employed by both qualitative and quantitative researchers. Brownes book is an exemplar of qualitative inquiry using purposeful sampling for applied research. The methodoloy of sampling and purposive sampling publish. Purposive sampling is a term used for methods of choosing a nonprobability sample in a way that makes it representative of the population, although there is no generally agreed definition of a representative sample, and purposive sampling is often based on subjective considerations. Pattons 40 purposeful sampling strategies visual brains.
Nonprobability sampling to learn more about nonprobability sampling, and sampling. Purposive sampling in qualitative circles is also referred to as nonprobability sampling. The issue of sample size in nonprobability sampling is rather ambiguous and needs to reflect a wide range of researchspecific factors in each case. Methods and appraisal for evidencebased practice, edition. Purposeful sampling the second case is quite different from the first. Purposive sampling, also known as judgmental, selective or subjective sampling, is a type of nonprobability sampling technique. Options include sampling from the range of eligible studies similar to purposively sampling participants within primary qualitative research or. Intensity sampling involves the same logic as extreme case sampling but with less emphasis on the extremes. Simple random sampling also referred to as random sampling is the purest and the most straightforward probability sampling strategy. The logic and power of purposive sampling, argues patton, lie in selecting. This type of sampling is actually employed by both qualitative and quantitative researchers, but because it is a nonprobability method, well discuss it in this section. This statement implies that the way that researchers sample must be tied. A form of nonprobability sampling in which decisions concerning the individuals to be included in the sample are taken by the researcher, based upon a variety of criteria which may include specialist knowledge of the research issue, or capacity and willingness to participate in the research. Purposive sampling an overview sciencedirect topics.
The first, and shorter, part of the book defines, discusses, and contrasts the three different types of sampling strategies available to researchers in the social sciences. And i was particularly happy to see that chapter 5 designing qualitative studies included 40 strategies you can use to do purposeful sampling. Briefly, theoretical sampling in grounded theory refers to the continual process by which cases are uncovered by. Choice an ideal reference for scientific researchers and other professionals who. An intensity sample consists of informationrich cases that manifest the. Convenience sampling technique is applicable to both qualitative and quantitative studies, although it is most frequently used in quantitative studies while purposive sampling is typically used in qualitative studies 5. Sampling and choosing cases in qualitative research sage.
Purposive sampling subjects are selected because of some characteristic. Sampling data and data collection in qualitative research, publisher. Dec 20, 2014 meaning and objective purposive sampling is a sampling method in which elements are chosen from among the whole population based on purpose of the study. Many qualitative studies, however, evolve to a purposive or purposeful sampling strategy in which researchers deliberately choose the cases or types of cases that will best contribute to the study. Purposive sampling article about purposive sampling by. The methodology of sampling and purposive sampling. It is the only book that takes a broad approach to sampling.
Purposive sampling may also be used with both qualitative and quantitative research techniques. It is also the most popular method for choosing a sample among population for a wide range of purposes. Meaning and objective purposive sampling is a sampling method in which elements are chosen from among the whole population based on purpose of the study. Cq press your definitive resource for politics, policy and people. Quantitative sampling strategies and techniques are random, which helps minimize the researchers bias the inherent disadvantage of qualitative sampling techniques. Sampling in qualitative research 2012 book archive. Qualitative data and sampling msw research methods. Purposive sampling of primary studies for inclusion in the synthesis is one way of achieving a manageable amount of data. It is easy to get a sample of subjects with specific characteristics.
Purposive sampling is used most often when a difficulttoreach population needs to be measured. Sage reference the complete guide for your research journey. These include purposive samples, snowball samples, quota samples, and convenience samples. Sampling in qualitative research sage research methods. Praise for the second edition this book has never had a competitor.
Additionally, researchers are able to draw on a wide range of qualitative research designs. In her book, browne purposefully sampled 11 of the women who killed their partners. As utilized in qualitative and mixed methods research, purposive sampling involves an iterative process of selecting research subjects rather than starting with a predetermined sampling frame. Pdf informed decisions about sampling are critical to improving the quality of research synthesis.
In particularly, i enjoy finding answers to many of my evaluation doubts in this book qualitative research and evaluation methods patton, 2015. Purposive sampling is a nonprobability sampling method and it occurs when elements selected for the sample are chosen by the judgment of the researcher. Sampling for qualitative research the aim of the qualitative research is to understand, from within, the subjective reality of the study participants. This innovative book critically evaluates widely used sampling strategies, identifying key theoretical assumptions and considering how empirical and theoretical claims are made from these diverse methods. Akin to grounded theory, the selection process involves identifying themes, concepts, and indicators through observation and reflection schutt, 2006. One of the more popular methods is called purposive sampling. All qualitative researchers sample, yet methods of sampling and choosing cases have received relatively little attention compared to other qualitative method. Sage video bringing teaching, learning and research to life. However, exhaustive sampling in a qualitative evidence synthesis has been questioned, and a more purposeful way of sampling papers has been proposed as an alternative, although there is a lack of transparency on how these purposeful sampling strategies might be applied to a qualitative evidence synthesis. Extreme or deviant case learning from highly unusual manifestations of the phenomenon of interest, such as outstanding successnotable. As utilized in qualitative and mixed methods research, purposive sampling involves an iterative process of selecting research subjects rather than starting with a.
A stratified purposeful sampling approach can lend credibility to a research study. Researchers often believe that they can obtain a representative sample by using a sound judgment, which will result in saving time and money. Quantitative methods are intended to achieve breadth of understanding while qualitative methods are for the most part. Who should you recruit for your qualitative research study. This paper is primarily based on literature research and it is divided among five parts, which are. Onwuegbuzie sam houston state university, huntsville, texas nancy l. Pdf sampling is a very complex issue in qualitative research as there are. Nick emmel presents a groundbreaking reworking of sampling and choosing cases in qualitative research. We discuss in our paper why and how we used purposeful sampling in a qualitative evidence synthesis about sexual adjustment to a cancer. Sage business cases real world cases at your fingertips.
Insights from an overview of the methods literature abstract the methods literature regarding sampling in qualitative research is characterized by important inconsistencies and ambiguities, which can be problematic for students and researchers seeking a clear and coherent understanding. When conducting quota sampling, a researcher identifies categories that are important to the study and for which there is likely to be some variation. Purposeful sampling for qualitative data collection and analysis in. Purposive sampling would seek out people that have each of those attributes. Qualitative sampling may begin with volunteer informants and may be supplemented with new participants through snowballing.
Raj, p10 such samples are usually selected with the help of random numbers. Feb 18, 2016 however, exhaustive sampling in a qualitative evidence synthesis has been questioned, and a more purposeful way of sampling papers has been proposed as an alternative, although there is a lack of transparency on how these purposeful sampling strategies might be applied to a qualitative evidence synthesis. Quota sampling is another nonprobability sampling strategy that takes purposive sampling one step further. This is contrary to probability sampling, where each member of the population has a known, nonzero chance of being selected to participate in the study necessity for nonprobability sampling can be explained in a way that for some studies it is not. The main advantage of purposive sampling is that a researcher can reach a targeted sample quickly. Scientific essay from the year 2012 in the subject business economics business management, corporate governance, language. Nonprobability sampling focuses on sampling techniques where the units that are investigated are based on the judgement of the researcher see our articles. Comparison of convenience sampling and purposive sampling.
Description as utilized in qualitative and mixed methods research, purposive sampling involves an iterative process of selecting research subjects rather than starting with a predetermined sampling frame. Nonprobability sampling is the most helpful for exploratory stages of studies such as a pilot survey. Much, but not all of the insight into the formulation and description of purposeful sampling arises from applied evaluation research. Purposive sampling is an acceptable kind of sampling for special situations. Qualitative and quantitative sampling types of nonprobability sampling nonprobability sampling typically used by qualitative researchers rarely determine sample size in advance limited knowledge about larger group or population types haphazard quota purposive snowball deviant case sequential populations and samples a population is any welldefined set of units of analysis. Sampling and data collection in qualitative studies. Purposive sampling as a tool for informant selection. In contrast to random methods of sampling, the purposive character of case.
1086 713 1123 872 252 479 573 535 13 513 876 969 1115 1001 747 716 1270 137 1258 86 281 731 1131 1468 1229 942 775 611 345 760