MODULE 10 Flashcards
is the extent to which the measurements used, often questionnaires, actually test the hypothesis or theory they are measuring.
Construct Validity
Threats to construct validity
- reactivity to the study situation
- researcher expectancies
- Noveity effects
- Compensatory effects
- Treatment diffusion or contamination
When people’s responses reflect, in part, their perceptions become part of the treatment construct under study There are several ways to reduce this problem, including blinding, using outcome measures not susceptible to reactivity (e.g. data from hospital records) and using pre-intervention strategies to satisfy participants’ desire to look competent or please the researcher.
Reactivity to the study situation
A similar threat stems from the researcher’s influence on participant responses through subtle (or not so-subtle) communication about desired outcomes. When this happens, the researcher’s expectations become part of the treatment (or nonmanipulated independent variable) construct that is being tested. Blinding is a strategy to reduce this threat, but strategy is to use observations during course of the study to detect verbal or behavioral signs or expectations
Researcher expectancies
When a treatment is new, participants and research agents alike might aller their behavior. People may be either enthusiastic or skeptical about new methods of doing things. Results may reflect reactions to the novelty rather than
to the intrinsic nature of an intervention, so the intervention construct is clouded by ____
Novelty effects
In intervention studies, _______ can occur if health care staff or family members try to compensate for the control group members’ failure to receive a perceived beneficial treatment. The compensatory goods or services must then be part of the construct description of the treatment conditions
compensatory equalization
is a related threat arising from the control group members’ desire to demonstrate that they can do as well as those receiving a special treatment.
Compensatory rivalry
Sometimes alternative treatment conditions can get blurred, which can impede good construct descriptions of the independents variable. This may occur when participants in a control group condition receive services similar to those available in the treatment condition.
Treatment diffusion or contamination
Threats to Statistical Conclusion Validity
Low statistical power
Restriction of range
Unreliable implementation of a treatment
are used to support inferences about whether relationships exist
Statistical Methods
refers to the ability to detect true relationships among variables. Adequate _____ can be achieved by using a sufficiently large sample. When small samples are used, statistical power tends to be low, and the analysis may fail to show that the independent and dependent variables are related, even when they are.
Statistical power
Another aspect of statistical power is _____. This is achieved through accurate measuring tools, controls over confounding variables, and powerful statistical methods.
precision
relationship between key research variables, it can be risky. Not only does this approach limit the generalizability of study findings, but it can also sometimes undermine statistical conclusion validity. When the use of homogeneity restricts the range of values on the outcome variable, relationship between the outcome and the independent variable will be attenuated, and may, therefore, lead to an erroneous inference that the variables are unrelated.
Restriction of Range
When the use of homogeneity restricts the range of values on the outcome variable, relationship between the outcome and the independent variable will be ______, and may, therefore, lead to an erroneous inference that the variables are unrelated.
attenuated
concerns the extent to which the implementation of an intervention is faithful to its plan. Interventions can be weakened by various factors, which researchers can often influence. One issue concerns the extent to which the intervention is similar from one person to the next. Usually, researchers strive for constancy of conditions in implementing a treatment because lack of standardization adds extraneous variation and can diminish the intervention’s full force.
Intervention fidelity, (or treatment fidelity)
Determining that intervention was delivered as intended may need to be supplemented with efforts to ensure that the intervention was received as intended. This may involve a ______ to assess whether the treatment was in place, was understood or was perceived in an intended manner
manipulation check
Another aspect of treatment fidelity for interventions designed to promote behavioral changes concern the concept of _____. _____ refers to participants’ performance of the treatment-related skilis, behaviors and cognitive strategies in relevant real-life settings
enactment
Another issue is that participants often fail to receive the desired intervention due to lack of _____. It is not unusual for those in the experimental group to elect not to participate fully in the treatment for example. they may stop going to treatment sessions. This might mean making the intervention as enjoyable as possible, offering incentives, and reducing burden in terms of the intervention and data collection
treatment adherence.
1.A pharmaceutical company is in a clinical trial of a new drug for COPD and the clients get excited, this can be a reactivity to situation under.
- A control group was being left behind when it comes to weight. A family member visited the facility where the research is ongoing and has given some of the subjects food and vitamins. This is called:
- A researcher has spoken to the participant in a study regarding her eagerness to find out the therapeutic effect of the new drug for COPD. This may result to what threat?
- Novelty effects
- Compensatory effects
- Researcher Expectancies
- Homogeneity may result to erroneous inference that variables are unrelated in
- A statistical power can be precise with the use of all of the following except
researcher expectancies
- When participants in a control group condition receive services similar to those available in the treatm threat is:
- Restriction of Range
- Researcher expectancies
- Treatment diffusion
7 Manipulation check is utilized by the researcher in what threat to statistical conclusion validity?
- It is a related threat arising from the control group members’ desire to demonstrate that they can do receiving a special treatment.
- To address this threat to validity, it is important to consider whether there will be sufficient participants support the statistical analyses envisioned.
- The degree to which inferences about relationships and differences from a statistical analysis of the data are accurate
- Unreliable implementation of treatment
- Compensatory rivalry
- Low statistical power
- Statistical Conclusion Validity
