Because of the multi-dimensional nature of constructs, their measurement is more complicated than other straightforward variables. Constructs often have no single, accepted definition; if the construct also has been used for some time, many diverse measurement scales may be available. Each dimension of the construct can be considered a variable in the study. For example, in the Pipe study (2008), the Functional Assessment of Chronic Illness Therapy is a scale used to measure general quality of life and has four dimensions: Physical Well-Being, Social/
Family Well-Being, Emotional WellBeing, and Functional Well-Being.
Being an Informed Consumer Of Research
How does the reader learn to be an informed consumer of research that includes measurement of constructs? The first step is to understand the theoretical framework chosen for the study and determine if the definitions of the constructs used by the researchers fit within this theory. Precise definitions of concepts and constructs used in the study and links with theory help to guide the research methodology and support accurate measurement (Corcoran, 2007). Watson's Theory of Caring supports the importance of the constructs for the nursing profession. As we review a study using constructs, we need to ask if the theory fits well with the study and if the study variables can be traced to the constructs and concepts in the theory. In addition, the definitions should make sense for the purpose of the study and the sample population.
The next step is to determine how the selected instruments fit with the definitions provided as well as with the study's population. Authors should report whether the instruments have been tested with the type of patient in the study. For example, the scale used by Pipe and colleagues (2008) measured general quality of life targeted at the management of chronic illness. This is appropriate for the type of patients in their study.
In addition, the reader will need to examine the material provided in the article on the validity of the instrument. Content validity indicates whether the instrument measures all the domains or content areas that make up the construct. Construct validity describes the instrument's ability to measure what it is supposed to measure. The reader will need to determine if the instrument is comprehensive enough to cover this construct. Is it a generic or diagnosis-specific instrument? Does the instrument include all the dimensions that reasonably could be expected to be in an instrument that will measure this construct (e.g., quality of life in hospitalized patients with chronic diseases)? If all the dimensions are not being used, do the researchers make a valid argument for exclusion of certain dimensions in this population? Has the instrument been tested for content and construct validity?
A summary of any validity and reliability testing should be included in the article with appropriate references. Depending on the reader's interest and purpose, he or she may need to review the references that outline the testing of the instrument in question. This would be important particularly if the reader is considering adopting an instrument for clinical assessment or a research study. Finally, the reader should review how the instruments were used in the study. Was the timing appropriate? Were the setting and situation appropriate? One of the interesting aspects of this study was that researchers measured these constructs over time and not just one point in time; they therefore could examine any change in the constructs (patient experiences) during and after hospitalization.
Understanding the nature of constructs is important when critiquing this kind of study. Precise definitions and solid measurement instruments add to the rigor and accuracy of a study. On the other hand, constructs can be modified over time as we learn more about them through research. Constructs are necessary for us to communicate about our patients within the profession of nursing. Patient-centered outcomes enhance our understanding of the patient experience and translate clinical improvement into patient-centered results (Wiklund, 2004).
Corcoran, M. (2007). From the desk of the editor: Defining and measuring constructs. American Journal of Occupational Therapy, 61(1), 7-8.
Pipe, T.B., Kelly, A., LeBrun, G., Smidt, D., Atherton, E, & Robinson, C. (2008). A prospective descriptive study exploring hope, spiritual well-being, and quality of life in hospitalized patients. MEDSURG Nursing, 17(4), 247-253, 257.
Salter, K.L., Moses, M.B., Foley, N.C., & Teasell, R.W. (2008). Health-related quality of life after stroke: What are we measuring? International Journal of Rehabilitation Research, 31, 111-117.
Wiklund, I. (2004). Assessment of patientreported outcomes in clinical trials: The example of health-related quality of life. Fundamental & Clinical Pharmacology, 18, 351-363.
Lynne M. Connelly, PhD, RN, is an Assistant Professor, University of Kansas, School of Nursing, and Clinical Nurse Researcher, University of Kansas Hospital, Kansas City, KS. She is Research Editor for MEDSURG Nursing.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||Research Roundtable; patient-centered assessment|
|Author:||Connelly, Lynne M.|
|Date:||Aug 1, 2008|
|Previous Article:||A prospective descriptive study exploring hope, spiritual well-being, and quality of life in hospitalized patients.|
|Next Article:||Using interdisciplinary shared governance and patient rounds to increase patient safety.|