Research design characteristics and components -pdf.pptx

research design objectives, research design characteristics, research design components, descriptive research design, analytical research design, observational research methods, experimental research methods.

1. Research design   By Suad Zuhair B. Pharm, M. Pharm. Clin.  Pharmacol .

2. Research design is a plan to answer your research question. Research design is a mapping strategy. Research design is the blue print for collection , measurement and analysis of data . It is a planning stages of research before getting the project underway, to visualize its practicability. Research design is a choice of an investigator about the components of his project. by Suad Zuhair, B. Pharm, M. Pharm.

3. Definition “Research design is a master plan specifying the methods and procedures for collection and analyzing the needed information.” William Zikmund Thus we can say that a research design is the arrangement of condition for collection and analysis of data in a manner that aims to generalize the findings of the sample on the population . by Suad Zuhair, B. Pharm, M. Pharm.

4. Components of research design A research design includes the following components : (a) The plan to answer the research problem. (b) Research method or research strategy. (c) Sampling design. (d) Data collection tools. (e) Data analysis techniques. by Suad Zuhair, B. Pharm, M. Pharm.

5. Purpose of a Research Design ( i ) To minimize the expenditure: provide maximum information with minimum spending of effort, money and time. (ii) To facilitate the smooth scaling (of the various research operations). (iii) To collect the relevant data and technique. (v) To provide an overview to other experts. (vi) To provide a direction. by Suad Zuhair, B. Pharm, M. Pharm.

6. Characteristics of Good Research Design ( i ) Objectivity: of the collected data: the data directly serves the needed objectives. (ii) Reliability: of the collected data: the data collected is consistent throughout a series of measurements. (reliability means repetition gives the same response) (iii) Validity: a measuring device, instrument, or test is said to be valid when it measures what it is expected to measure. (so this specific method or instrument is only valid for specific purpose) e.g IQ test is only valid for intelligence testing. by Suad Zuhair, B. Pharm, M. Pharm.

7. (iv) Generalizability: data collected from the samples can be utilized for drawing certain generalizations applicable to a large group from which sample is drawn. (representative sample for the population derived from) (v) Adequate Information: the collected data provide the adequate information needed to answer the research problem or test the hypothesis. (vi) Other Features: flexibility, adaptability, efficiency, being economic and so on. by Suad Zuhair, B. Pharm, M. Pharm.

8. a) The plan The first step in a research design is to deicide  How you want to answer your research problem? To answer this question researcher should deicide the nature of the findings he wants to find, either: 1) Descriptive or 2) Analytical i.e. the problem will be solved in descriptive or analytical form. by Suad Zuhair, B. Pharm, M. Pharm.

9. Aspect Descriptive Research Analytical Research Objective Describe and document characteristics or phenomena. Analyze and interpret data to understand relationships or causality. Focus “What” questions “Why” and “How” questions Data Analysis Summarizing information Statistical research, hypothesis testing, qualitative research Goal Provide an accurate and comprehensive description Gain insights, make inferences, provide explanations or predictions Causal Relationships Not the primary focus Examining underlying factors, causes, or effects by Suad Zuhair, B. Pharm, M. Pharm.

10. Aspect (continue) Descriptive Research Analytical Research Data collected Qualitative (mostly) or quantitative Quantitative or quantitative Research approach Mostly Cross-sectional Cross-sectional or longitudinal Intervention or manipulation level Observational (no intervention) Observational or experimental Examples Surveys, case study/series Experiments, cohort, case-control, surveys, and case study/series by Suad Zuhair, B. Pharm, M. Pharm.

11. Descriptive Research design Descriptive research describes the characteristics of the population or phenomenon studied. Primarily focuses on demographics “the various characteristics of a population” without focusing on “why” a particular phenomenon occurs. In other words, it “describes” the research subject without covering “why” it happens. Gives answers about: what? Develop new facts . by Suad Zuhair, B. Pharm, M. Pharm.

12. Analytical research design Determines the causal connections between two or more variables. Aims to identify the causes and mechanisms underlying a specific phenomena. Aids in proving the validity of a theory or supporting a hypothesis. It assists in recognizing a claim and determining whether it is true. Find out why something occurs is complex. Gives answer about: why, how, which, or when? Develop new ideas by Suad Zuhair, B. Pharm, M. Pharm.

13. b) Research method or research strategy A research method is a strategy used to implement the plan. Broudy (1963) stated that “Method refers to the formal structure of the sequence of acts commonly denoted by instruction.” Research techniques are ways of implementing a method. Different techniques may be employed within the same method. So method is more general, it includes techniques also. There are two main categories of research methods: observational or experimental . by Suad Zuhair, B. Pharm, M. Pharm.

14. *Observational research methods: Observe and systematically record behaviors, events, or phenomena without directly manipulating them . [No intervention] They DESCRIBE or found ASSOCIATION between variables but can not prove casual relationships (that one thing causes another). Represent a strategy to implement both descriptive and analytical research designs. by Suad Zuhair, B. Pharm, M. Pharm.

15. Types of observational research methods: Case study or case series Survey method Case-control method Cohort method by Suad Zuhair, B. Pharm, M. Pharm.

16. *Experimental research methods: Experimental studies are ones where researchers introduce an intervention and study the effects. Represent a strategy to implement analytical research designs. Types of experimental methods: Controlled trails. Randomized controlled trials. Randomized single-blind controlled trials. Randomized double-blind controlled trials. by Suad Zuhair, B. Pharm, M. Pharm.

17. Case study method - A single case of a particular phenomenon is examined intensively for the light that it can shed on a specific problem or question. -Used to examine a proposed theory or to provide grounded and detailed information for a new theory. -Gives a scientifically driven descriptions of a singular incident or disease. [Descriptive designs] -Gives special implications for theoretical analysis (or inference) . [Analytical designs] -They are limited in their generalizability and can not provide statistical inferences. Example: a case study for a new side effect happened after drug marketing, a case study for an infection by a new strain of virus, or a new resistant strain of bacteria. by Suad Zuhair, B. Pharm, M. Pharm.

18. Advantages 1) In-depth analysis of complex phenomena. 2) Holistic Understanding (from multiple angles). 3) Examination of rare and Unusual Phenomena. 4) Supports the generation of new theories or hypotheses. 5) Ideal in Situations where Researchers cannot Control the Variables Disadvantages 1) Not Usually Generalizable. 2) Subjectivity in interpretation. 3) Difficulty in replicating results. Because the study takes place in complex real-world settings where variables are not controlled. by Suad Zuhair, B. Pharm, M. Pharm.

19. Survey method -Survey research is defined as "the collection of information from a sample of individuals through their responses to questions“. -Survey research can use quantitative research strategies (e.g., using questionnaires with numerically rated items), qualitative research strategies (e.g., using open-ended questions), or both strategies (i.e., mixed methods). -The primary purpose of this type of survey research was to obtain information describing characteristics of a large sample of individuals of interest relatively quickly. [descriptive surveys] -Also may attempt to describe and explain why certain situations exist. In this approach two or more variables are usually examined. [analytical research] Example: demographic and personal characteristics and consumer feedback surveys. by Suad Zuhair, B. Pharm, M. Pharm.

20. In order to ensure a high-quality survey process and outcome , researcher should consider the following: who to include (representative sample), what and how to distribute (survey tool), and when to initiate the survey and follow up with nonresponders (reducing nonresponse error). by Suad Zuhair, B. Pharm, M. Pharm.

21. Advantages 1) Easy to develop 2) Cost-effective 3) Can be developed in less time 4) Capable of collecting data from a large number of respondents. 5) Numerous questions can be asked about a subject, giving extensive flexibility in data analysis Disadvantages 1) Has a cross sectional nature of data, which fail to represent time-varying variables. 2) Respondents may not feel encouraged to provide accurate, honest answers. 3) Recall bias 4) Surveys with closed-ended questions may have a lower validity rate than other question types. 5) Data errors due to different number of respondents who choose to respond from those who chose not to respond. 6) Survey questions with answer options could lead to unclear data because certain answer options may be interpreted differently by respondents. by Suad Zuhair, B. Pharm, M. Pharm.

22. Case control method -A case-control study is a type of observational study commonly used to look at factors associated with diseases or outcomes. -The case-control study starts with a Group Of Case Individuals who have the outcome of interest . -The researcher then construct a second Group Of Individuals Called The Controls , who are similar to the case individuals but do not have the outcome of interest . -The researcher then looks at historical factors to identify if some exposure (s) is/are found more commonly in the cases than the controls . - If the exposure is found more commonly in the cases than in the controls, the researcher can hypothesize that the exposure may be linked to the outcome of interest. by Suad Zuhair, B. Pharm, M. Pharm.

23. Example: A researcher may want to look at the rare cancer Kaposi's sarcoma. The researcher would find a group of individuals with Kaposi's sarcoma (the cases) and compare them to a group of patients who are similar to the cases in most ways but do not have Kaposi's sarcoma (controls). The researcher could then ask about various exposures to see if any exposure is more common in those with Kaposi's sarcoma (the cases) than those without Kaposi's sarcoma (the controls). The researcher might find that those with Kaposi's sarcoma are more likely to have HIV, and thus conclude that HIV may be a risk factor for the development of Kaposi's sarcoma. by Suad Zuhair, B. Pharm, M. Pharm.

24. Advantages of case control method Allows for the study of rare diseases. For example, if a disease developed in 1 in 1000 people per year (0.001/year) then in ten years one would expect about 10 cases of a disease to exist in a group of 1000 people. Makes it possible to look at multiple risk factors at once. In the example about Kaposi's sarcoma, the researcher could ask both the cases and controls about exposures to HIV, asbestos, smoking, lead, sunburns, aniline dye, alcohol, herpes, and others to identify those most likely associated with Kaposi's sarcoma. Helpful with disease outbreaks , when potential links and exposures need to be identified. or Helpful when rare diseases start to increase in frequency. Disadvantages of case control method Recall bias Recall bias in a case-control study is the increased likelihood that those with the outcome will recall and report exposures compared to those without the outcome. Cannot establish causation . The case group (those with the outcome) and the control group (those without the outcome) should have almost the same characteristics . Confounding bias Occurs when a variable (intervening/confounding) that is not being accounted for that has a relationship with both the exposure and outcome. by Suad Zuhair, B. Pharm, M. Pharm.

25. Cohort method -A cohort study is a type of observational study which starts with a group of people with a certain exposure and a second group do not have the exposure then followed over time to find how many reach a certain outcome of interest. -The researcher looks if the outcome of interest is found more commonly in the exposed group than the unexposed group. -The outcome of interest could be disease, condition, event, death, or a change in health status or behavior. -This method is used to estimate the cumulative incidence and incidence rate . -These studies may be prospective, retrospective, or both. -Cohort study has a longitudinal nature of data, which is a strength point because of time-varying variable. by Suad Zuhair, B. Pharm, M. Pharm.

26. Example: Framingham cohort study This cohort study was initiated in 1948 in Framingham. Framingham, at the time of initiation of the cohort, was an industrial town 21 miles west of Boston with a population of 28,000. This Framingham Heart Study recruited 5209 men and women (30–62-year-old) in the study to assess the factors associated with cardiovascular disease (CVD). The researchers also recruited second generation participants (children of original participants) in 1971 and the third general participants in 2002. This has been one of the landmark cohort studies and has contributed immensely to our knowledge of some of the important risk factors for CVD. The investigators have published 3064 publications using the Framingham Heart Study data. by Suad Zuhair, B. Pharm, M. Pharm.

27. Prospective cohort study In this type of cohort study, the data are collected directly from participants. Participants are classified as exposed or unexposed at present time. Then participants are followed directly to assesses the outcome of interest. At baseline and during follow-up, the investigator also collects information on other variables that are important for the study (such as confounding variables). Retrospective cohort study In this type of cohort study, the data are collected from records . participants are classified as exposed or unexposed from records at past time. Then records are followed to assesses the outcome of interest. Other variables are also identifies at baseline and during follow up. by Suad Zuhair, B. Pharm, M. Pharm.

28. by Suad Zuhair, B. Pharm, M. Pharm.

29. Advantages 1) Can study multiple outcomes in the same exposure. one exposure (hypercholesterolemia) and multiple outcomes (melasma and psoriasis) 2) Prospective cohort study measures the exposure variable and outcomes more accurately (no recall bias). 3) Retrospective cohort studies are fast and relatively inexpensive compared with a prospective cohort studies. Disadvantages 1) Prospective cohort design is time consuming and costly. 2) In a retrospective cohort study, the exposure and the outcome variables are collected before the study has been initiated. Thus, the measurements may not be very accurate or according to our requirements. 3) Cohort studies may not be very efficient for rare outcomes (like case-control) except in some conditions (if the rare outcome is common in some exposures). by Suad Zuhair, B. Pharm, M. Pharm.

30. Controlled trails An experiment or clinical trial in which two groups are used for comparison purpose. The comparison (control) group receives a placebo , another treatment , or no treatment at all . A controlled experiment is an experimental setup designed to test hypotheses . Controlled experiments are difficult to design and analyse , as they should be designed to have: a) Reliability (Would you get the same measurement again?) b) Validity (Are you measuring what you claim to be measuring?) by Suad Zuhair, B. Pharm, M. Pharm.

31. c) Internal validity is the relationship between your measurement and what you think it tells you about the experimental task. d) External validity is the relationship between what you measure in the lab, and the phenomenon in the outside world. To check that the experimental design procedure is right , every experiment should first include at least one or several pilot studies . A Preliminary data analysis for the pilot study results can be conducted to ensure internal validity. Pilot study results will be discarded from the final data analysis. To have good external validity , the recruited participants should be representative of the population about which we want to make research conclusions. by Suad Zuhair, B. Pharm, M. Pharm.

32. Informed consent: A 'consent form’ prepared by experimenters, stating the nature of the experiment and the rights of the participant . Before the start of the experiment , participants should be asked to read this form, and sign it to indicate that they have read and understood their rights. Participant briefing: Participant should be given the same instructions before the commence of the experimental task, briefing instructions are normally written out in full, in order to ensure that the task is done. Debriefing: At the end of an experimental session, participants should normally be debriefed. Debriefing involves a short interview, often semi-structured, with some prepared questions. Because they might well be able to warn you of potential problems with task validity, from their perception of the task. Incentives and compensation: It is recommended to compensate participants for their time, although compensation need not be financial . People may be very willing to participate in experiments from which they gain interesting feedback, or experiments that are intrinsically enjoyable (for example games). A token gift (chocolates, a book or report, software, or a memento such as copies of a scan) may be sufficient reward. by Suad Zuhair, B. Pharm, M. Pharm.

33. Data Retention: If the data collected contains personal data , then they fall within the terms of the Data Protection Ac t. Personal data should be kept secure. Significant ethical issues: If your experiment involves any of the following activities, it will need to consult the relevant ethics committee and to take clearances: a) Experiments involving animals . b) Medical and other invasive experiments on human participants. c) Psychological manipulation of human participants (deception, emotional manipulation, etc.). by Suad Zuhair, B. Pharm, M. Pharm.

34. A randomized controlled trial Is an experiment in which participants are assigned at random to different conditions(groups), in order to test in an objective way which of several alternatives is superior. A randomized double blind controlled trial A type of clinical trial in which neither the participants nor the researcher knows which treatment or intervention participants are receiving until the clinical trial is over. This makes results of the study less likely to be biased. While in single blind trails only participants didn’t know. by Suad Zuhair, B. Pharm, M. Pharm.

35. "سبحان الله" by Suad Zuhair, B. Pharm, M. Pharm.