Research 36-377 Dr. Wally J. Bartfay

1. Research 36-377Dr. Wally J. Bartfay “When the solution is simple…God is answering” (Albert Einstein, 1879-1955)

2. Observational Measurement • Although most common in qualitative research, it is used to some extent in all types of studies (e.g., esp. with children) • Measurement in qualitative research is not distinct from analysis b/c tend to occur simultaneously

3. Observational Measurement • Not as simple as it sounds • Have to 1st decide what is to be observed • 2nd, need to determine how to ensure that every variable is measured consistently in same manner • Tend to be more subjective so less credible method • Must pilot test technique & interrater reliability

4. Unstructured observations • Involves spontaneous observing & recording with little prior planning • Certain risk of loss of objectivity here • Notes are usually taken during observation period or shortly after • “Chronologs” are detailed descriptions of subjects in a natural environment {very intense so can’t record for more than 30 mins at a time} • Some studies, video-recordings may be made

5. Structured Observations • 1st step is to define exactly what is to be observed • 2nd step, need to determine how observations will be recorded & coded • Often a “category system” is developed for organization & sorting behavior or events, which are mutually exclusive (e.g., infant is eating, sleeping, playing, running, climbing, sitting) • Checklists are also used to tally-up how often behaviors or events occur

6. Questionnaires • Are printed self-report forms designed to elicit specific information (e.g., knowledge, attitudes, intentions, opinions etc) • Subject can’t elaborate, so can be a limitation • If response rate is less than 50% (esp. with mailed-type), the representativeness is in question • Can employ strategies to increase response rates (e.g., multiple mailings, monetary incentive, prizes)

7. Scales • Types of self-report, more precise than questionnaires & is based on mathematical theory • Rating scales are crudest form (e.g., rate pain on scale of 1 to 10) • Likert scales are designed to determine “degree and magnitude” of opinions or attitudes on various topics (e.g., strongly disagree, disagree, neutral, agree & strongly agree) • Visual analogue scales (VAS) or magnitude scales (subject asked to place mark on vertical or horizontal line following a specific question)

8. The concepts of measurement in research: Nominal scales • 4 levels 1st described by Stevens (1946): “NOIR” • (1) Nominal-scale measurement: data organized into categories but not ranked (e.g., gender, ethnicity, marital status, Dx) • All categories are exclusive & exhaustive • Note: when data are coded for entry into a data base, they are typically coded (e.g., 1 = male, 2 = female), but importantly, 1 is not higher or greater than 2 here)

9. The concepts of measurement in research: Ordinal-scales • (2) Ordinal-scale measurement: can be assigned ranked categories (e.g., levels of mobility, self-care, daily amount of exercise) • however, it CAN’t be demonstrated that intervals between categories are equal in nature (hence, unequal intervals here) • Sometimes called “ordered metric scales” • All categories are exclusive & exhaustive • E.g., Exercise intensity can be ranked as: 1 = mild exercise- no SOB, no perspiration; 2 = moderate exercise, mild SOB, no perspiration, and 3 = strenuous exercise, SOB with perspiration

10. The concepts of measurement in research: Interval-scales • (3) Interval scales: Distances between intervals are numerically equal, & assumed to be a “continuum of values” • However, has absence of a “zero point” so not a true absolute scale (e.g., temperature, can’t say that “0” means absence of temp)

11. The concepts of measurement in research: Nominal scale • (4) Ratio-scales: highest form, have all criteria of previous including mutually exclusive & exhaustive categories, rank ordering, equal spacing between intervals & continuum of values + have “absolute zero” (e.g.,pulse, wt. & ht.) • Zero pulse means the absence of pulse; moreover, b/c of absolute zero, one can say that pulse of 150 is twice as fast as one of 75 beats per minute

12. Physiological Measures • Can be either direct or indirect, where direct are more valid • E.g., measurement of arterial pressure waveforms through an arterial catheter provides a direct measurement of blood pressure, whereas use of stethoscope & sphygmomanometer provides an indirect measure

13. Historical Research: • Is a systematic approach for understanding past events through the collection, organization & critical appraisal of facts • Its goal is to shed light on the past so that it can guide the present & future • Primary sources: 1st –hand eyewitness accounts (e.g., diaries, filmed interviewed) • Secondary sources: provide view of phenomenon from another’s perspective rather than 1st hand account

14. Multimethod Component Designs: • Here, qualitative & quantitative aspects are implemented as separate & discrete components for the overall study • These components remain separate & discrete during data collection, interpretation & reporting of outcomes

15. Multimethod Integrated Designs: • (1) Iterative designs: involve a dynamic in which findings from one method used to move foreword & refine alternative method (e.g., one instrument used to development & refine other instrument) • (2)Nested or embedded designs: one methodological approach is embedded in the other • (3) Holistic designs: multiply methods are integrated simultaneously rather than hierarchically • (4) Transformative designs: better suited to theory building, emphasis is on “blending” different research traditions to arrive at a better representation of the larger social context

16. Epidemiology • Term derived from Greek “epi” =upon & demos = people; logos = science • Study of “epidemics” • Investigate how various states of health are distributed in populations & what environmental conditions, life-styles or other circumstances are associated with presence or absence of diseases • Patterns of symptoms often “cluster” in a particular age group, geographical area or time period (1st clue in learning what the “cause” is)

17. Epidemiology: historical roots • Since antiquity, people have attempted to explain what “causes” disease/ illness • Often attributed to supernatural events • Hippocrates (460-377 BC) attempted to explain disease on a rationale basis • In several books (“Airs, Waters & Places, Epidemics I & II”),he pointed-out that disease is a mass phenomena & noted that environment & lifestyle are related to occurrence of disease

18. Natural History of Disease • Is a process by which diseases occur & progress in the human host, involves 3 factors: • (1) Agent: is a factor whose presence causes a disease or one whose absence causes disease (chemical, biological) • (2) Environment: refers to all external & internal conditions & influences affecting the live of living things (physical, socioeconomic, biological environment) • (3) Host: human in whom an agent produces disease

19. Causal relationships: • Direct causal association: those in which a factor causes a disease with no other factor intervening • Causal factor  Outcome • E.g., Tubercule bacillus  Tuberculosis

20. Causal relationships: • Indirect causal associations: 3rd intervening variable, occupies an intermediate stage between the cause & effect • A B C  D • E.g., Cigarette smoke (A) damages respiratory epithelium (B); this then increases susceptibility of epithelium to infection (C); & this results in chronic bronchitis

21. The Disease Process • Occurrence of disease in human host is not a single event at one point in time, but a process • “Clinical horizon”: imaginary line dividing the point where there are detectable signs & symptoms form that were there are not • Disease process natural Hx. Is divided into 2 board periods: (i) Prepathogenesis & (ii) Pathogenesis

22. Prepathogenesis Period: • (1) Susceptibility: • (a) interrelations of various host, agent, & environmental factors bring host & agent(s) together • (b) Disease-provoking stimulus is produced in the known host (remains asymtomatic) • (2) Adaptation: processes are initiated • Research emphasis here is “primary prevention” (e.g., health promotion/ education, immunizations, sanitation, removing occupational hazards, dietary nutrients etc)

23. Pathogenesis Period: • (1) Presymptomatic disease/ Early pathogenesis stage • (a) Interaction of host & stimulus continue after failure of adaptive response (e.g., immune system is ineffective) • (b) Stimulus or agent becomes established (e.g., if infectious agent, increases by multiplication) • (c) Start of tissue & physiological changes

24. Pathogenesis Period: • (2) Discernible early lesions stage: • (a) Clinical recognition of disease is possible via lab or other Dx. Tests to detect early physiological changes • (b) Pt. develops early symptoms that go unrecogized as problematic • Research emphasis here is “secondary prevention” (e.g., early Dx. & screening, prompt Rx., case finding)

25. Pathogenesis Period: • (3) Clinical Disease stage: • (a) Acute illness • (b) Disability • (c) Defect • (d) Chronic state • (e) Death • Research emphasis here is on Rx. to arrest disease process (e.g., meds, surgery) & “tertiary prevention” (e.g., rehab. retraining r/t ADL post stroke)

26. “That’s all folks!”