Critical Review Form for Quantitative Studies
Student Name: Laura Vogtle Date: 1/10/04
Kondo, T., Mann, W. C., Tomita, M., & Ottenbacher, K. (1997). The use of microwave
ovens by elderly persons with disabilities. American Journal of Occupational
Therapy, 51, 739 – 747.
STUDY PURPOSE: Outline the purpose of the study. How does the study
Was the purpose stated apply to your research question?
Yes X The purpose of this research to demonstrate the
No impact of microwave oven use on the appliances
used in cooking, meal preparation duration and
kinds of foods prepared in elderly persons with
LITERATURE: Describe the justification of the need for this study.
Was relevant background
literature reviewed? Described restrictions caused by arthritis and
Yes X visual impairments
No Discussed impact of these restrictions on ability to
Discussed popularity and use of microwave ovens,
and their application as assistive technology.
DESIGN: Describe the study design. Was the design appropriate for
Randomized (RCT) the study question? (e.g., for knowledge level about this
Cohort issue, outcomes, ethical issues, etc.)
Single case design X
Before and after This is a single subject study, withdrawal design,
Case-control ABAB format. The design is appropriate because
Cross-sectional there is no research about the use of these ovens in
Case study elderly persons with a disability. Single subject
design allows for an experimental approach to
treatment in a pilot study format the will give
information about the efficacy of the treatment.
Specify any biases that may have been operating and the
direction of their influence on the results.
We don’t know who did the random phone call checks,
which might have influenced the outcomes. The
researchers were from a grant-funded program in assistive
technology. The program may have used these subjects in
SAMPLE: Sampling (who, characteristics, how many, how was
N= 5 sampling done?) If more than one group, was there
similarity between the groups?
Was the sample described 5 subjects, 4 women and 1 man, all over age 60.
in detail? Disabilities were arthritis; arthritis complicated by heart
Yes X disease, asthma and residual from a stroke; impaired
No mobility with pain, lower limb weakness, and fatigue;
pigmentary retinitis; diabetic retinopathy and glaucoma,
arthritic pain and heart disease. All were chosen from a
pool at University of New York at Buffalo. No subjects
had cognitive impairments.
Was sample size justified? Describe ethics procedures. Was informed consent
N/A X Not mentioned
OUTCOMES: Specify the frequency of outcomes measurement (i.e., pre,
Outcome measures data was recorded daily and
collected weekly throughout all four phases of the
Were the outcome measures Standardized assessments were not used to
reliable? measure outcomes.
Yes X outcomes measured were; number of appliances
No used in meal preparation, the number of different
Not addressed foods prepared, and the length of time spent on
These outcome data were measured by frequency
counts on number of appliances and kinds of
foods; duration of meal preparation was timed by
the participants. All data was reported by
Were the outcome measures participants and checked by random reliability
valid? checks done by phone.
Yes Reliability and validity: Reliability of participant reporting
No was carried out by using phone calls to check on
Not addressed X frequency of using cooking appliances, number of
different foods prepared, and length of time needed for
meal preparation. Correlation coefficients ranged from
.88-.99 for frequency of use,
.83 - .98 for different kinds of foods and .91 - .99 for
length of time it took to cook a meal.
INTERVENTION: Provide a short description of the intervention (focus, who
Was intervention described delivered it, how often, setting). Could the intervention be
in detail? replicated in practice?
No Subjects were given basic instruction in use, safety, food
Not addressed preparation and appropriate containers prior to
intervention. Intervention consisted of provision of a
microwave oven. Data collection was via subject
completed logs done on a daily basis. Data logged
included number of appliances used in meal preparation,
kinds of food prepared, and the duration of cooking time.
The same data was collected across all 4 phases. The first
A phase was for baseline data collection and the second A
phase was withdrawal of the oven. The B phases were the
times when the oven was placed in the home. Duration of
each phase was 3 weeks. Logs were collected on a weekly
basis. This intervention could have been easily carried out
in a clinical setting except for the random reliability
checks performed by phone call. Frequency of checks
was not reported, nor do we know who carried out these
Was contamination Subjects were chosen from the same sample pool and
avoided? there is a slim chance some of them may have known each
Yes other and discussed the research. If any of the subjects
No received therapy services at SUNY-B, they may have
Not addressed X heard about the research from therapists working there. In
N/A the process of receiving training in microwave use, it was
possible subjects could have met each other or heard
therapists discuss the study.
Was cointervention Subjects may have participated in senior nutrition centers
avoided? and received information on meal preparation there.
Yes Family members may have known about the study and
No encouraged/discouraged participants to use ovens. Three
Not addressed X subjects had never used a microwave but two had.
N/A Previous experiences may have affected their performance
in the study.
RESULTS: What were the results? Were they statistically significant
Were results reported in (i.e., p <0.05)? If not statistically significant, was the
terms of statistical study big enough to show an important difference if it
significance? should occur? If there were multiple outcomes, was that
Yes taken into account for the statistical analysis?
N/A X Data analysis was carried out by graphing the data, use of
Not addressed descriptive statistics on each of the dependent variables,
and inclusion of means on each variable graph across all
Were the analysis method(s) phases.
Yes X Study findings: Overall, the study demonstrated that
No subjects needed less time to prepare a wider variety of
Not addressed foods. Study results were affected by illness to some
subjects and by life events. One subject who liked to cook
increased the time she spent cooking due to
experimentation with different foods. Subjects felt
microwave ovens were safer than regular ovens.
Shortening cooking times meant less time standing for
those participants who had weakness and pain in the lower
Was clinical importance What was the clinical importance of the results? Were
reported? differences between groups clinically meaningful? (if
Yes X applicable)
Not addressed The outcomes of the study were clinically meaningful.
There was a marked difference in each of the dependent
variables between treatment and withdrawal phases of the
Were drop-outs reported? Did any participants drop out from the study? Why?
Yes (Were reasons given and were drop-outs handled
No X appropriately?)
No dropouts, although several subjects were ill during the
study and unable to participate as much as others.
CONCLUSIONS AND What did the study conclude? What are the implications
CLINICAL of these results for practice? What were the main
IMPLICATIONS: limitations or biases in the study?
Were conclusions The study demonstrated a measurable affect of microwave
appropriate given study ovens on meal preparation and diet of elderly persons with
methods and results? disabilities. The outcomes could have been affected by
Yes X previous cooking experiences, the fact that subjects were
No required to document information, making them more
aware of what they were eating. The sample size is small,
making generalizability to larger populations hard.
Law, M., Stewart, D., Letts, L., Pollock, N., Bosch, J., & Westmorland, M. (1998).
Critical review form for quantitative studies. Retrieved March 14, 2002, from