Quasi-experimental studiesStudies of cause and effect similar to experimental design but using convenience samples or existing groups to test interventions.Random errorA nonreproducible error that can arise from a variety of factors in measurement.Random selectionA method of choosing a random sample using mathematical probabilityto ensure the selection of subjects is completely objective.Randomized controlled trialAn experiment in which subjects are randomly assigned to groups, one of which receives an experimental treatment while another serves as acontrol group. The experiment has high internal validity so the researcher can draw conclusions regarding the effects of treatments.RangeA measure of variability that is the distance between the two most extreme values in the data set.RateA calculated count derived from dividing the frequency of an event in agiven time period by all possible occurrences of the event during the same time period.RecontextualizingA qualitative data analysis and cognitive process undertaken by the researcher to search for meaning that may lead to a theory.ReflexivityA sensitivity to the ways in which the researcher and the research process have shaped the data; based on introspection and acknowledgment of bias.ReplicabilityThe likelihood that qualitative research outcomes or events will happenagain given the same circumstances.ReplicationRepeating a specific study in detail on a different sample. When a study has been replicated several times and similar results are found, the evidence can be used with more confidence.Replication study
A study generated from previous research studies in which the research is reproduced to validate findings, increase generalizability, oreliminate or minimize limitations.Research designThe overall approach to or outline of the study that details all the majorcomponents of the research.Research questionA question that outlines the primary components to be studied and that guides the design and methodology of the study.Respect for personsA basic principle of ethics stating that individuals should be treated as autonomous beings who are capable of making their own decisions. Persons who have limited autonomy or who are not capable of making their own decisions should be protected.ResponsivenessA measure that indicates change in the subject’s condition when an intervention is effective.Retrospective studiesStudies conducted using data that have already been collected about events that have already happened. Such secondary data were originally collected for a purpose other than the current research.Reversal designsSingle-subject designs that continue to measure the response of the individual as the intervention is withdrawn or withdrawn and reinitiated.