Selected study design in research method
- 1. Selecting a Study Design (Part II) Week 5
- 2. Types of study design
- 3. Study designs based on the nature of the investigation • experimental; • non-experimental; • quasi- or semi-experimental.
- 4. • If a relationship is studied in the way, starting from the cause to establish the effects, it is • classified as an experimental study. • If the second path is followed – that is, starting from the effects to trace the cause – it is classified as a non-experimental study
- 6. • A semi-experimental study or quasi- experimental study has the properties of both experimental and non-experimental studies; part of the study may be non-experimental and the other part experimental.
- 7. • An experimental study can be carried out in either a ‘controlled’ or a ‘natural’ environment. • For an experiment in a controlled environment, the researcher (or someone else) introduces the intervention or stimulus to study its effects. • The study population is in a ‘controlled’ situation such as a room. • For an experiment in a ‘natural’ environment, the study population is exposed to an intervention in its own environment.
- 8. Experimental study designs • the after-only experimental design; • the before-and-after experimental design; • the control group design; • the double-control design; • the comparative design; • the ‘matched control’ experimental design; • the placebo design.
- 9. • Panel study is: • an investigation of attitude changes using a constant set of people and comparing each individual's opinions at different times.
- 10. • Suppose you want to study the changes in the pattern of expenditure on household items in a community. • To do this, you would select a few families to find out the amount they spend every fortnight on household items. • You would keep collecting the same information from the same families over a period of time to ascertain the changes in the expenditure pattern.
- 11. Constructing an Instrument for Data Collection
- 12. Quantitative and Qualitative Research Methods of Data Collection
- 13. • The distinction is mainly due to the restrictions imposed on flexibility, structure, sequential order, depth and freedom that a researcher has in their use during the research process. • Quantitative methods favour these restrictions whereas qualitative ones advocate against them.
- 14. • if an observation is recorded in a narrative or descriptive format, it becomes qualitative information, but if it is recorded in categorical form or on a scale, it will be classified as quantitative information. • If data collected through interviews. An unstructured interview, recorded in a descriptive or narrative form, becomes a qualitative method, but in a structured interview, if the information is recorded in response categories or if the categories are developed and quantified out of descriptive responses, it is a quantitative method.
- 15. • Descriptive responses obtained in reply to open-ended questions are all qualitative but if the responses are in numerals they will be considered quantitative.
- 16. Major approaches to information gathering
- 17. • primary sources provide first-hand information and secondary sources provide second-hand data. • Examples of primary sources include finding out first-hand; • the attitudes of a community towards health services, • ascertaining the health needs of a community, • evaluating a social program, • determining the job satisfaction of the employees of an organisation, and • ascertaining the quality of service provided by a worker
- 18. • the use of census data to obtain information on the age–sex structure of a population, • the use of hospital records to find out the morbidity and mortality patterns of a community, • the use of an organisation’s records to ascertain its activities, and • the collection of data from sources such as articles, journals, magazines, books and periodicals to obtain historical and other types of information, are all classified as secondary sources.
- 19. • Several methods can be used to collect primary data. The choice of a method depends upon the purpose of the study, the resources available and the skills of the researcher.
- 20. • Observation is one way to collect primary data. Observation is a purposeful, systematic and selective way of watching and listening to an interaction or phenomenon as it takes place. • There are many situations in which observation is the most appropriate method of data collection;
- 21. • It is also appropriate in situations where full and/or accurate information cannot be elicited by questioning, because respondents either are not co-operative or are unaware of the answers because it is difficult for them to detach themselves from the interaction.
- 22. • when you are more interested in the behavior than in the perceptions of individuals, or • when subjects are so involved in the interaction that they are unable to provide objective information about it
- 23. • Types of observation • There are two types of observation: • 1. participant observation; • 2. non-participant observation.
- 24. • Participant observation • is when you, as a researcher, participate in the activities of the group being observed in the same manner as its members, with or without their knowing that they are being observed. • For example, you might want to examine the reactions of the general population towards people in wheelchairs. • You can study their reactions by sitting in a wheelchair yourself. Or • you might want to study the life of prisoners and pretend to be a prisoner in order to do this.
- 25. • Non-participant observation, • is when you, as a researcher, do not get involved in the activities of the group but remain a passive observer, watching and listening to its activities and drawing conclusions from this. • For example, you might want to study the functions carried out by nurses in a hospital. As an observer, you could watch, follow and record the activities as they are performed.
- 26. Problems with using observation method • When individuals or groups become aware that they are being observed, they may change their behaviour. Depending upon the situation, this change could be positive or negative – it may increase or decrease, for example, their productivity – and may occur for a number of reasons. • There is always the possibility of observer bias. If an observer is not impartial, s/he can easily introduce bias and there is no easy way to verify the observations and the inferences drawn from them. • The interpretations drawn from observations may vary from observer to observer. • There is the possibility of incomplete observation and/or recording. An observer may watch keenly but at the expense of detailed recording.
- 27. The interview • Any person-to-person interaction, either face to face or otherwise, between two or more individuals with a specific purpose in mind is called an interview. • According to Monette et al. (1986: 156), ‘an interview involves an interviewer reading questions to respondents and recording their answers’. • According to Burns (1997: 329), ‘an interview is a verbal interchange, often face to face, though the telephone may be used, in which an interviewer tries to elicit information, beliefs or opinions from another person’.
- 28. • When interviewing a respondent, you, as a researcher, have the freedom to decide • the format and content of questions to be asked of your respondents, • select the wording of your questions, • decide the way you want to ask them and • choose the order in which they are to be asked.
- 30. • Structured interviews • In a structured interview the researcher asks a predetermined set of questions, using the same wording and order of questions as specified in the interview schedule. • An interview schedule is a written list of questions, open ended or closed, prepared for use by an interviewer in a person-to-person interaction (this may be face to face, by telephone or by other electronic media).
- 31. The questionnaire • A questionnaire is a written list of questions, the answers to which are recorded by respondents. • In a questionnaire respondents read the questions, interpret what is expected and then write down the answers. • The only difference between an interview schedule and a questionnaire is that in the former it is the interviewer who asks the questions (and if necessary, explains them) and records the respondent’s replies on an interview schedule, and in the latter replies are recorded by the respondents themselves.
- 32. • In the case of a questionnaire, as there is no one to explain the meaning of questions to respondents, it is important that the questions are clear and easy to understand. • Also, the layout of a questionnaire should be such that it is easy to read and pleasant to the eye, and the sequence of questions should be easy to follow. • A questionnaire should be developed in an interactive style.
- 33. • Advantages of a questionnaire • It is less expensive. As you do not interview respondents, you save time, and human and financial resources. The use of a questionnaire, therefore, is comparatively convenient and inexpensive. • It offers greater secrecy. As there is no face-to-face interaction between respondents and interviewer, this method provides greater anonymity. – In some situations where sensitive questions are asked it helps to increase the likelihood of obtaining accurate information.
- 34. • Disadvantages of a questionnaire • Application is limited. One main disadvantage is that application is limited to a study population that can read and write. It cannot be used on a population that is illiterate, very young, very old or handicapped. • Response rate is low. Questionnaires are notorious for their low response rates; that is, people fail to return them. • There is a self-selecting bias. Not everyone who receives a questionnaire returns it, so there is a self-selecting bias. • Opportunity to clarify issues is lacking. • It is possible to consult others. • A response cannot be supplemented with other information.
- 35. Forms of question • open-ended question the possible responses are not given. – In the case of a questionnaire, the respondent writes down the answers in his/her words, but in the case of an interview schedule the investigator records the answers. • closed question the possible answers are set out in the questionnaire or schedule and the respondent or the investigator ticks the category that best describes the respondent’s answer.
- 36. Constructing a research instrument in quantitative research • Step I – Clearly define and individually list all the specific objectives, research questions or hypotheses, if any, to be tested. • Step II – For each objective, research question or hypothesis, list all the associated questions that you want to answer through your study. • Step III – Take each question that you identified in Step II and list the information required to answer it. • Step IV – Formulate question(s) that you want to ask of your respondents to obtain the required information.