Quiz 2: Research Design

what are quantitative assumptions?

have a single objective reality, investigator and object of study are independent, goal is to develop generalizable characteristics of reality, causes and effects can be determined and differentiated, objectivity, numeric data

what are qualitative assumptions?

multiple constructed realities, investigator and subject are interdependent, knowledge is time and context dependent, impossible to distinguish between causes and effects, subjectivity, non numeric data

what are quantitative research approaches?

assumes that the truth is objective and can be revealed by independent investigators, stats are used to determine the answer, greater control leads to high study quality, traditional scientific method, deductive reasoning, can be subject level or study level

what are subject level approached?

experimental, quasi-experimental, and non-experimental

what are study level approaches?

systematic reviews, meta-analysis, health technology assessment, and clinical practice guideline

what are characteristics of an experimental study?

has purposeful manipulation of subjects, two or more groups of subjects, and random assignment of subjects to groups

what are characteristics of quasi-experimental studies?

has purposeful manipulation of subjects, may have only 1 group, non random assignment to groups

what are characteristics of non-experimental studies?

no real time manipulation of subjects, may have only one group of subjects, non-random assignment to groups

what is a between subjects design?

research design where there is comparison between independent groups of subjects

what is a within subjects design?

research design where repeated measures are taken within the same subjects

what is a cross sectional study?

a study in which data is collected at a single point in time or limited time period

what is a longitudinal study?

study in which there is repeated data collection over an extended period of time, is non experimental and usually prospective (though can be retrospective), requires sufficient time to achieve outcome, demonstrates the relationship between predictor and outcome, also is expensive normally

what is a retrospective study?

A study that looks back at data or events that have already occurred, historical data is used to answer research question w

what is a prospective study?

A study that follows participants forward in time, collecting data on outcomes as they occur (data collected in real time to answer research question)

what are the controls of a study that can be used to minimize bias?

subjects, equipment, environmental conditions, testing and/or training administration, data collection and recording, and communication (though more control results in less generalizability for clinical practice)

what is bias?

results that systematically deviate from the truth, errors that distort data (examples are selection bias, measurement bias, and responder bias)

what are the different types of research questions?

questions about diagnosis, prognosis and risk factors, clinical tests and measures and instruments, interventions, clinical prediction rules, test clusters, treatment based classification, outcomes

what are cross sectional studies used for?

determine the prevalence of something, describe the features of a population (diagnosis), understand determinants of health, reliability and validity test/measures, doesn’t permit distinction between cause and effect but is relatively efficient study design

what is a longitdinal/cohort design used for?

used to study incidence, cause, and prognosis

what is a case control study used for?

useful for studying rare diseases or outcomes, identifying risk factors by comparing cases with controls, causality

what are the characteristics of a case control design?

usually retrospective, has 2 groups- one with the outcome and one without, looked back over time to see what percent of each group have exposure to or factor of interest, subjects are matched to controls known to be free out the outcome, the two groups should be identical except for outcome status since other differences could be confounders

what is efficacy compared to effectiveness?

efficacy is when the intervention produces outcome under ideal conditions, and effectiveness is when the intervention produces outcomes under clinical conditions (clinically relevant)

what are the characteristics of a randomized control trial?

a experimental design that randomly assigns participants to either the intervention or control group, minimizes bias, allows for causal inference, and ideally uses blinding to reduce placebo effects. large subject pools are preferred, and considered the gold standard in interventions research

what are the pros and cons of RCTs?

pros: randomization reduces the effects of confounders, but cons are expensive and lengthy

what are the characteristics of a factorial design?

an experimental design in which multiple factors are investigated, each with two or more levels, allowing for the evaluation of interactions between factors and their individual effects on the outcome. (single factor, two factor, and multi-factor)

what are types of quasi-experimental designs?

time series design and non-equivalent control group design

what are the characteristics of a time series design?

A quasi-experimental design that involves repeated measurements over time before and after an intervention of a single group, allowing for the analysis of trends and effects without random assignment.

what are the characteristics of a non-equivalent control group design?

A quasi-experimental design that compares outcomes between naturally occurring groups, with baseline characteristics unlikely to be equal between the groups

what are the characteristics of a narrative review?

a study level design that analyzes individual studies as a literature review, considered lower level of evidence with less rigorous methodology, is often opinion based to support a particular point of view, may or may not have established search and selection methods, limited to no critical analysis of individual studies included in the review

what are the characteristics of a systematic review?

a study level design that is a true research study with defined designed features (specific research question, inclusion and exclusion criteria, standardized review, eval of quality of articles included) considered high level of evidence (ex: Cochrane Collaboration or PEDro), summarizes and evaluates entire literature on a topic, identifies knowledge gaps

what are the pros and cons of systematic reviews?

pros: includes multiple studies, cons: compromises made to present the data

what are the characteristics of a scoping review?

A study level design that maps the existing literature on a topic, identifies gaps in research, and summarizes key concepts, usually without restricting to study quality. possible a first step before a systematic review or research. not limited to peer review literature, more exploratory with qualitative synthesis of the literature

what are the characteristics of a meta-analysis?

a form of a systematic review, pools data of multiple studies for additional statistical analyses, increased sample size and statistical power of analysis

what are the pros and cons of meta-analysis studies?

pros: increase statistical power, cons: compromises made to combine data, data from individual studies are often unable to be combined or are inappropriately combined

what is a health technology assessment?

summarizes literature on a topic from efficacy, safety, and economic perspective

what are the pros and cons of health technology assessments?

pro: comprehensive approach, con: expensive/lengthy

what is a clinical practice guideline?

Systematically developed statements to assist practitioner and patient decisions about appropriate healthcare for specific clinical circumstances, utilizes findings from other levels of evidence and study designs, usually formulated by consensus of experts

what is the goal of qualitative research approaches?

understand meaning people assign to their experiences, produces rich and detailed description in whihc depth is more important than breadth, results focus on themes or patterns of data, and data is reported in narrative rather than statistical format

how might data be collected for qualitative research approaches?

interviews, surveys, diaries, observations, etc

what are the three major design orientations of qualitative research?

ethnographic designs that focus on cultural patterns, phenomenological designs that focus on finding meaning from the viewpoint of a small group of subjects, and grounded theory that seeks to understand social, psychological, and structural processes within the context of experiences

what kind of reasoning does qualitative research use?

inductive, differs from quantitative in lack of hypotheses or focus on outcomes