Week 5: Chapters 9 and 18

personal interview, telephone interview, self-administered questionnaire

modes of collecting survey data

clinical trials, evaluation research, nursing intervention research

studies that involve an intervention

history threat

other events co-occurring with causal factor that could also affect outcomes

selection bias, expectancy effect, enhanced internal validity

threats to external validity

low statistical power, weakly defined cause, unreliable implementation of a treatment

threats to statistical conclusion validity

cause must precede the effect, must be a demonstrated empirical relationship between the cause and effect, relationship cannot be explained by a third variable

three criteria for making causal inferences

nonequivalent control group, within-subjects

two main categories of quasi-experimental designs

case-control design

"cases" (e.g., those with lung cancer) are compared to "controls" (e.g., those without lung cancer) on prior potential causes (e.g., smoking habits).

experimental

INTERVENTION + RANDOMIZATION+ CONTROL

quasi-experimental

INTERVENTION BUT MISSING RANDOMIZATION OR CONTROL

nonexperimental

If there is no intervention, the study is ___________.

quasi-experiments

Involve an intervention but lack either randomization or control group

control

The researcher introduces controls, including the use of a control group.

selection threat

This is the single biggest threat to studies that do not use an experimental design

nonequivalent control group designs

Those getting the intervention are compared with a nonrandomized comparison group.

time series designs

gather pre-intervention and post-intervention data over longer period

phase 1

phase in a clinical trial that finalizes the intervention (includes efforts to determine dose, assess safety, strengthen the intervention)

phase 4

phase in a clinical trial that focuses on long-term consequences of the intervention and on generalizability; sometimes called an effectiveness study

phase 3

phase in a clinical trial that fully tests the efficacy of the treatment via a randomized clinical trial (RCT), often in multiple sites; sometimes called an efficacy study

phase 2

phase in a clinical trial that seeks preliminary evidence of effectiveness—a pilot test; may use a quasi-experimental design

maturation threat

processes that result simply from the passage of time

make the groups equal with regard to all other factors except receipt of the intervention

purpose of randomization

random assignment

putting subjects in random groups once you have them in your study

random sampling

random subjects pulled from population

outcome research, surveys, secondary analysis, methodologic research

studies that do not involve an intervention

single blind

subjects don't know which group they are in (e.g., placebo or sham used)

descriptive correlational research

the purpose is to describe whether variables are related, without ascribing a cause-and-effect connection.

selection bias

the sample selected for the study does not accurately represent target population.

temporal ambiguity

unclear whether presumed cause occurred before outcome

statistical conclusion validity

the ability to detect true relationships statistically

internal validity

the extent to which it can be inferred that the independent variable caused or influenced the dependent variable

external validity

the generalizability of the observed relationships to the target population

cross-sectional data

Data are collected at a single point in time

outcome analysis

Seeks preliminary evidence about program success

intervention fidelity

whether the treatment as planned was actually delivered and received.

correlational design

Cause-probing questions (e.g., prognosis or harm/etiology questions) for which manipulation is not possible are typically addressed with a:

longitudinal design

Data are collected two or more times over an extended period.

outcomes research

Designed to document the quality and effectiveness of health care and nursing services

between-subjects design

Different people are compared

evaluation research

Examines how well a specific program, practice, procedure, or policy is working

factorial design

More than one independent variable is experimentally manipulated

experimental condition

Must be designed with sufficient intensity and duration that effects might reasonably be expected

nonexperimental

NO INTERVENTION; observational or descriptive May have random SAMPLING—NOT same as random ASSIGNMENT!

survey research

Obtains information (via self-reports) on the prevalence, distribution, and interrelations of variables in a population

outcomes research

Often focuses on parts of a health care quality model developed by Donabedian

within-subjects designs

One group is studied before and after the intervention.

pretest-posttest design

Outcome data collected both at baseline and after the intervention

posttest only design

Outcome data collected only after the intervention

A

Researchers tested whether Healing Touch sessions would reduce anxiety among patients with cancer. Which of the following is an example of a threat to the study's internal validity? A. Study participants had low baseline anxiety levels. B. The study sample was too homogeneous. C. The study was conducted in the country of Turkey. D. There is no proof that Healing Touch reduces anxiety

B

Researchers wonder whether providing healthier food choices in a middle school cafeteria and vending machines would reduce total caloric intake and percent of sugar and salt students consume. They compare students' baseline daily calorie, salt and sugar intake before and after introducing healthier food and beverage choices. Why is this considered a quasi-experimental rather than an experimental study? A. There is no intervention. B. There is no random assignment. C. It is prospective. D. It's only done in one school.

within-subjects design

Same people compared at different times or under different conditions

survey research

Secures information about people's actions, intentions, knowledge, characteristics, opinions, and attitudes

clinical trials

Studies that develop clinical interventions and test their efficacy and effectiveness

methodologic research

Studies that focus on the ways of obtaining, organizing, and analyzing data

secondary analysis

Study that uses previously gathered data to address new questions

crossover design

Subjects are exposed to 2+ conditions in random order; subjects "serve as their own control"

biologic plausibility

The causal relationship should be consistent with evidence from basic physiologic studies.

coherence

The evidence about the existence of a relationship should come from multiple sources

randomization/random assignment

The researcher assigns subjects to groups at random.

manipulation

The researcher does something to some subjects—introduces an intervention (or treatment).

B

Which of the following is an example of a mortality threat to the internal validity of a study? A. Survey sent to 1500 nurses with 1200 completing the questionnaire. B. 100 subjects enrolled to test effects of text messaging to improve diet with 70 completing. C. Study comparing length of stay in the ICU preceding discharge to hospice versus no-hospice for patients with advanced cancer. D. 30 subjects complete a smoking cessation study.

B

Which of the following is most likely to be an example of a "true experiment"? A. "The effects of sunlight exposure on Vitamin D levels in preschool children: A retrospective study." B. "The impact of melatonin on sleep regulation in blind adults: A randomized, placebo-controlled study." C. "National survey of children's second-hand smoke exposure in households of smoking adults." D. "Comparison of hospitals with Magnet status versus those without on nursing turnover."

A

Which of the following provides the best example of meeting criteria to determine causality? A. Intestinal distress occurs after subjects diagnosed with Celiac disease ingest gluten. B. Intuition that computer screen time impairs vision. C. Prospective study showing high correlation between stress and anxiety. D. Increased sodium intake predicted to lower blood pressure.

B

Which of the following research methods is most appropriate to answer the research question: "What is the daily protein intake of homeless inner-city adults?" A. Phase I study B. Face-to-face survey C. Phase IV study D. Telephone survey

A

Which of the following studies is most likely to provide evidence of a cause and effect relationship? A. Double-blind, randomized controlled trial of peppermint oil for improving IBS symptoms. B. Retrospective chart review examining predictors of depression in nursing home residents. C. Living with chronic fatigue syndrome: A Grounded Theory study. D. Survey of patients' understanding of routine hospital discharge instructions.

A

Which phase of development is the following clinical trial most likely to be? "Pharmacokinetic study to determine dose levels of the anti-diabetic agent AGN29." A. Phase I B. Phase II C. Phase III D. Phase IV

prospective correlational design

a potential cause in the present (e.g., experiencing vs. not experiencing a miscarriage) is linked to a hypothesized later outcome (e.g., depression 6 months later).

correlation

an association between variables and can be detected through statistical analysis.

retrospective correlational design

an outcome in the present (e.g., depression) is linked to a hypothesized cause occurring in the past (e.g., having had a miscarriage).

longitudinal data

are better at showing patterns of change and at clarifying whether a cause occurred before an effect

randomized control trial

best type of study to prove causality

selection threat

biases arising from pre-existing differences between groups being compared

prospective designs

called a cohort study by medical researchers

mortality threat

differential loss of participants from different groups (by dropping out for any reason)

structure of care, processes, outcomes

key concepts of outcomes research

retrospective

looking backward

prospective

looking forward

expectancy effect

makes effects observed in a study unlikely to be replicated in real life.

randomization, subjects as own controls, homogeneity, matching, statistical control

methods on controlling intrinsic factors

double blind

neither researchers nor subjects know what group subjects are assigned to

experimental designs

offer the strongest evidence of whether a cause (an intervention) results in an effect (a desired outcome).