Principles Of Dietetics - topic C: research applications

Question 1

steps in research

Answer 1

1. identify a relevant and important topic: review published research literature related to the topic
2. develop well-considered research question (who, what, how)
   - clear, simple statement in a few words, in a complete grammatical statement
3. research question leads to a hypothesis
   - measurable, specifies population being studied, time frame, type of relationship being examined, defines variables being studied, states level of statistical significance
4. prepare research protocol: methodology to solve the problem
5. study design and checklists

Question 2

meta analysis

Answer 2

is a formal, defined system that combines the results of numerous small studies to increase the strength of belief in the observed effect. Studies are of similar design, have defined inclusion and exclusion criteria, and are published peer-reviewed studies

Question 3

meta-analysis - QUOROM

Answer 3

has proposed quality standards for the review and monitoring of systematic reviews and meta-analysis of randomized trials. Companion standards that suggest common evaluation criteria for clinical trials

Question 4

meta-analysis - PRISMA

Answer 4

randomized control trials. PRISMA is an evidence-based minimum set of items for reporting in systematic reviews and meta-analyses. PRISMA focuses on the reporting of reviews evaluating randomized trials, but can also be used as a basis for reporting systematic reviews of other types of research, particularly evaluations of interventions

Question 5

meta-analysis - MOOSE

Answer 5

meta-analysis of Observational Studies in Epidemiology

Question 6

meta-analysis - CONSORT

Answer 6

Common criteria (guidelines) for clinical trials

Question 7

Research report - results

Answer 7

specific lab, clinical, objective or subjective findings

Question 8

Research report - discussion

Answer 8

interpretation of results, comparison with other studies; may be combined with results. discussing the results addresses the research question, objective and hypothesis. places results in context of existing science, implications for future research or clinical practice, limitations and strengths

Question 9

Research report - implications

Answer 9

how the information might be applied in practice

Question 10

descriptive research

Answer 10

• describes state of nature at a point in time
• generates hypotheses regarding determinants of a condition or disease- does not prove cause and effect - describes a situation

Question 11

descriptive research- surveys

Answer 11

research designed to describe and quantify characteristics of a defined population; defined time frame; pinpoints problems

Question 12

descriptive research - correlation studies or ecological studies

Answer 12

describe and don’t prove
- compare frequency of events (or disease rates) in different populations with the per capita consumption of certain dietary factors (correlation between fish consumption and breast cancer incidence)

Question 13

analytical research

Answer 13

• randomization is dividing people into treatment or control groups without bias
• experimental group receives the program or treatment
• control group does not receive the treatment or may receive a placebo which gives the aura but not the substance of a service, removing the possibility of a Hawthorne effect (positive response due to attention that participants receive). In a study of aspartame, sugar might be the placebo.
• program is successful if the experimental group has improved more than the control group

Question 14

analytical research - gold standard

Answer 14

clinical nutrition studies: RCT (randomized controlled trial) with comparison placebo control group is the gold standard. this is considered the best for evaluating medical treatments, and intervention with one or more treatments.

Question 15

analytical research - quasi-experimental design

Answer 15

time series - series of measurements at periodic intervals before the program begins and after the program ends (note worthy change). it shows whether measurements before and after the program are a continuation of previous patterns or whether they indicate a noteworthy change - no control group

Question 16

analytical research - cohort studies

Answer 16

• sometimes called incidence studies tracking the frequency of new cases (newly diagnosed) of a disease
• cohort- any group whose members have something in common
• carried out over a long period of time (longitudinal), and prospective (future-oriented)
• can also be restrospective

Question 17

analytical research - cross-sectional studies / prevalence

Answer 17

• all existing cases at that time (prevalence)
• one time data collection counting all of the cases of a specific disease among a group of people at a particular time.
• describes current events

Question 18

IRB - institutional review board (under FDA)

Answer 18

committee established to review and approve research involving human subjects to ensure it is conducted within all ethical and federal guidelines

Question 19

what do you need to do to be designated as an author or a manuscript in a biomedical journal?

Answer 19

you must have made substantial contributions to the design or analysis and the interpretation of the data.

Question 20

statistical evaluation, interpretation and application - internal validity

Answer 20

tests whether the difference between the two groups is real (has the experimental group really performed differently) - how valid is it internally

Question 21

statistical evaluation, interpretation and application - external validity

Answer 21

tests whether or not a generalization can be made from the study to a larger population - how valid is it externally

Question 22

statistical evaluation, interpretation and application - analysis of variance - ANOVA

Answer 22

• validity 3 or more samples
• used when several (three or more products) compete against one another
• answers: are there one or more significant differences anywhere among the samples

Question 23

statistical evaluation, interpretation and application - reliability

Answer 23

consistency or reproducibility of test results
- test then retest later; are the results similar? the more similar, the more reliable

Question 24

statistical evaluation, interpretation and application - nominal variable

Answer 24

(non-ordered) - variables that fit into a category with no special order (gender, race, marital status, present or absent)

Question 25

statistical evaluation, interpretation and application - rank order variable

Answer 25

(ordinal scale) - observations compared with each other and put in order, perhaps from best to worst, or state of disease from 1 to 4

Question 26

statistical evaluation, interpretation and application - dependent vs. independent variables

Answer 26

dependent are outcomes; independent variables are what you manipulate in your study
- treatments for diseases are independent variables (you can change the treatment to affect the disease)
- effect cholesterol levels (independent) have on heart attacks (dependent)

Question 27

statistical evaluation, interpretation and application - sampling - probability

Answer 27

uses randomization - select a sample form the whole population so the characteristics of each of the units approximates the characteristics of the whole population

Question 28

statistical evaluation, interpretation and application - non-probability

Answer 28

no way of forecasting that each element in the population will be represented in the sample

Question 29

measuring data distributions - measures of central tendency

Answer 29

• center of any mass of data
  1. arithmetic mean - simple average. total the values of all observations and divide by the number of observations
  2. median - midpoint. arrange observations from low to high; count the number of values. median is the value at the midpoint.
  3 mode - most frequently occurring value; prediction most likely to be right. repeated number

Question 30

measuring data distributions - measures of dispersion

Answer 30

• how values are distributed about the mean
  1. range - difference between the lowest and highest values in the distribution
  2. standard deviation - indicates degree of dispersion about the mean value of a distribution
• about 2/3 (68%) of all observations in a normal distribution lie within 1 SD of the mean - this range is called M + 1 SD of the mean (Mean + 1 SD)

Question 31

existence of relationships

Answer 31

• correlations are relationships between varying types of data
• value of r is always between -1 and 1
• the closer r is to 1 or -1, the closer the points tend to cluster about the line, and the stronger the degree of linear relationship
• 1.1 and 1.2 are not valid answers
• perfect agreement or positive correlation is +1.0; perfect negative correlation is -1.0
• r =1 positive slope upward to the right
• r = -1 negative slope upward to the left
• closer dots are to the line = stronger the pull

Question 32

clinical significance

Answer 32

lower p-value, higher significance of results

Question 33

double blind study

Answer 33

removes bias from research; neither the researcher nor the subject knows which group is receiving the treatment and which the placebo

Question 34

mortality / morbidity

Answer 34

rate of death; state of disease

Question 35

inferential statistics

Answer 35

techniques that allow conclusions to extend beyond an immediate data set; what is the probability that the results can be applied to a larger group; what can you infer from the results of your study

Question 36

pilot study

Answer 36

scaled down version of the larger investigation; practice implementation, determine whether clinical trial, as planned, is feasible; are goals realistic and attainable? includes every step in the study, but done on a small test group. will the study plan work? formative evaluation

Question 37

focus group

Answer 37

method of attaining information about a target group; small group who talk about the beliefs, opinions, problems; contributes attitudinal data; subjective

Question 38

qualitative research / quantitative research

Answer 38

asks why and how (subjective); asks how many, how often (objective)

Question 39

use of evidence analysis as a basis for practice decisions

Answer 39

evidence-based guidelines are developed by conducting a systematic review and then using the conclusion of the review to develop practice-based guidelines. subject matter experts and trained analysts summarize best available evidence. the AND evidence analysis library assists in answering questions that may arise during the provision of nutrition case. based on scientific evidence.