EAL

MHFS: Food Safety (2012-2013)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To investigate the food safety knowledge, psychosocial factors and self-reported behaviors of young adults with education beyond high school.

Inclusion Criteria:

College students in introductory-level general education courses from across the United States.

Exclusion Criteria:

Participants older than the age criterion set in this study for young adults (17 to 26 years).

Description of Study Protocol:

Recruitment

Instructors were invited via e-mail to recruit students to complete an online food safety survey. In return for their participation in the study, students who participated were awarded extra credit points or research credits required by the course by most participating instructors.

Design

Cross-sectional study.

Statistical Analysis

Analysis of central tendency and dispersion were conducted to describe the study participants and mean scores for each behavior, psychosocial and knowledge measure
To identify demographic characteristics associated with performance on behavior, psychosocial and knowledge measures, backward stepwise regression with an exclusion criterion set at an F value ≥ 25 was conducted
This low P value was chosen because of the large size of the survey sample
For demographic factors found to be consistently and significantly related to scores on study measures, analysis of variance and post-hoc Fisher's protected least significant difference follow-up procedures were used to investigate how the mean scores of demographic groups differed; the criterion for significance was set at P≤0.02 because of the large sample size.

Data Collection Summary:

Timing of Measurements

January to October 2005.

Dependent Variables

Best practice
Risky food consumption
Five belief scales
Three locus of control scales
Self-efficacy
Stage of change
Knowledge.

Independent Variables

Gender
Race
Geographic location of the college or university where the participant was enrolled
Number of meals cooked weekly
Number of nutrition, microbiology and food science courses completed in college
Stage of change (except when it was a dependent variable)
Whether the participant had ever worked as a food server or preparer
Whether the participant believed he or she had experienced food poisoning before and had changed eating habits because of food safety concerns
The predominant locus of control was another independent variable used in all models except in those with a locus of control scale score as the dependent variable.

Control Variables

Marital status
Year in college
Age
College major
Health status
Self-assessment of food safety knowledge and skills
Where they first learned about food safety.

Description of Actual Data Sample:

Initial N: 4,343 young adults
Attrition (final N): 4,343
Age: Mean age was 19.92±1.67 years
Ethnicity:

Race	Percent
White	70%
Black	5%
Hispanic	4%
Asian/Pacific Islander	18%
American Indian	1%
Multiracial	1%
Other	<1%

Other relevant demographics: 65% female, 35% male, 94% single
Location: United States.

Summary of Results:

Key Findings

Behavior Measures

The Cronbach alpha coefficients of internal consistency for the best practices and risky food consumption questionnaires were 0.65 and 0.76, respectively, indicating that both scales were reliable for assessing intended measures
Overall, participants' best practices scores were poor, averaging less than 50%. To identify specific problem areas, sub-scores were calculated for items that measured similar practices:

Best Practices	Score
Cross-contamination prevention	44.5±12
Disinfection and cleaning	49.1±26.7
Thermometer use and temperatures for cooking, reheating and storing food	48.3±17.5
Food storage	33.5±17.1
Hand washing	52.2±27.7

Although best practices scores were low, higher self-rated food safety skill levels corresponded with significantly higher best practices scores
Risky food consumption scores indicated that participants ate few "high-risk" foods:

Food	Percentage
Raw bivalve shellfish	11%
Raw sprouts	29%
Sushi	29%
Fried eggs with soft yolks	33%
Raw cookie dough	53%

Eating undercooked meats was reported as follows:

Undercooked Meat	Percentage
Bacon	43%
Pork	44%
Chicken	51%
Hamburger	60%

A comparison of the best practices and risky food consumption scores by gender showed that females scored significantly better than males on all scales. Overall, females handled food more safely and ate fewer risky foods than males.
An examination of behavior measures by stage of change indicated that those in lower stages had significantly poorer best practices scores than those in higher stages. Likewise, those in pre-action stages tended to eat significantly more risky foods than those in the action or maintenance stage.

Psychosocial Measures

Factor analysis confirmed the unidimensionality of the food safety belief and locus of control scales. The belief and self-efficacy scales were judged to be valid and reliable. The locus of control scales exhibited the same high qualities of validity; however, the reliability coefficients were somewhat lower. Nonetheless, the locus of control reliabilities was similar to that reported for the instrument on which it was modeled, namely the health focus of control.
Here are the psychosocial scale scores:

Measure	Reliability	Score
Food Safety Beliefs
Interest in learning about avoiding food poisoning	0.86	3.65±0.72
Cleanliness/sanitation is important	0.81	4.48±0.55
Food poisoning susceptibility	0.76	3.88±0.56
Food poisoning is a threat in the United States	0.87	3.69±0.62
Food poisoning is a personal threat	0.87	3.12±0.81
Food safety locus of control
Internal	0.63	3.72±0.81
External: Powerful others	0.63	3.34±0.83
External: Chance	0.59	2.88±0.76
Food safety self-efficacy	0.93	4.13±0.55
State of change		2.65±1.21

Participants were most uncertain about whether food poisoning was a personal threat for them with males tending to somewhat disagree. Females had significantly more positive belief scores than males.
Those in the pre-contemplation and contemplation stages tended to have significantly lower belief scores than those in higher stages, whereas those in the maintenance stage tended to have significantly higher mean belief scores than those in lower stages
A comparison of locus of control scores indicated that regardless of stage of change, most believed that their actions affected their likelihood to avoid food-borne disease
Locus of control was as follows:

Locus of control	N	Percentage
Internal	2,386	54.9%
External: Powerful others	1,234	28.4%
External: Change	539	12.4%
No single predominant	184	4.2%

Participants had a significantly higher (P<0.0001) mean score on the internal scale than the external: powerful others and external: chance scales. The mean external: powerful other scale score was significantly higher (P<0.0001) than the mean external: chance scale score. Females and males scores differed significantly on only the external: chance scales. Those in the precontemplation stage tended to have significantly lower external; powerful others scores and higher external: chance scores.
Self-efficacy scores were high, indicating participants had a high level of confidence in their ability to handle food safely. Females significantly outscored males on this scale. Those in higher stages tended to have significantly greater self-efficacy scores than those in lower stages.
A review of stage of change data showed that young adults hover between the contemplation and preparation stage when it comes to preparing food to make it safe to eat. Overall, females had a significantly more advanced stage of change.

Knowledge Measure

The reliability of the knowledge test was high (0.92 as computed by Livingston's coefficient for criterion-referenced tests)
Overall, participants correctly answered 60% of the questions on the knowledge measure
As with the best practices measure, knowledge sub-scores were calculated for items measuring similar concepts
The sub-scores showed that participants were most knowledgeable about groups at greatest risk for food-borne disease and were least knowledgeable about common food sources of food-borne disease pathogens
Females scored significantly higher than males on all areas of knowledge except for the common food sources of food-borne disease pathogens
Participants in the maintenance stage of change significantly outperformed all other stages on the knowledge measures
Although food safety knowledge was limited, higher self-rated food safety knowledge levels tended to correspond with significantly higher mean knowledge scores.

Author Conclusion:

This study provided insights into the food safety self-reported behaviors and cognitions of young adults enrolled in college. Overall, young adults have less than optimal levels of food safety knowledge and safe-handling best practices. Best practices and knowledge mean scores declined significantly as self-rated food safety knowledge levels declined, respectively. However, even those with excellent self-ratings achieved mean scores of only about 50 and 60% on best practices and knowledge measures, respectively. These findings suggest that young adults accurately assess their food safety skills and knowledge relative to peers, but most over-estimate their actual abilities.
On the plus side, young adults, particularly females, generally have a limited intake of foods that increase the risk of food-borne illness, positive food safety beliefs, an internal locus of control and positive feelings of self-efficacy. They are also contemplating an improvement in or preparing to improve their food-handling practices. Those in higher stages of change tended to perform better on all measures than those in lower stages of change.
Although there are many studies on this general topic, few studies focus on the age group described in this study. This study is useful in providing baseline data regarding the food safety knowledge of young adults, an audience that is important to reach with safe food handling education messages because of their current and future roles as caregivers for household members. Efforts to improve knowledge and ultimately food-safety behaviors are essential to safeguard the health of these young adults and to enable them to fulfill the role of protecting the health of their future families. Bridging the gap between what young adults know and do in relation to food safely and their positive psychosocial characteristics is the next step in food safely education efforts directed to young adults.

Funding Source:

Government:

U.S Department of Agriculture, National Food Safety Initiative grant

Reviewer Comments:

The authors note the following limitation:

The sample was restricted to young adults enrolled in a small sampling of colleges in the United States. However, these students were distributed across the nation, attended colleges and universities of varying sizes with widely varying admission requirements and had a similar age and demographic breakdown compared with recent post-secondary education enrollment statistics.

Quality Criteria Checklist: Primary Research
Relevance Questions
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes

Validity Questions
1.	Was the research question clearly stated?		Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.3.	Were the target population and setting specified?	Yes
2.	Was the selection of study subjects/patients free from bias?		Yes
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	Yes
	2.2.	Were criteria applied equally to all study groups?	Yes
	2.3.	Were health, demographics, and other characteristics of subjects described?	Yes
	2.4.	Were the subjects/patients a representative sample of the relevant population?	???
3.	Were study groups comparable?		N/A
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	N/A
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	N/A
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	N/A
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	N/A
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	N/A
4.	Was method of handling withdrawals described?		Yes
	4.1.	Were follow-up methods described and the same for all groups?	Yes
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	N/A
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.4.	Were reasons for withdrawals similar across groups?	N/A
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	N/A
5.	Was blinding used to prevent introduction of bias?		N/A
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	N/A
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	N/A
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	N/A
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	N/A
6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?		Yes
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	N/A
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	N/A
	6.6.	Were extra or unplanned treatments described?	N/A
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	N/A
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	N/A
7.	Were outcomes clearly defined and the measurements valid and reliable?		Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	Yes
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	Yes
	7.7.	Were the measurements conducted consistently across groups?	N/A
8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?		Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	Yes
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	Yes
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	N/A
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	Yes
	8.6.	Was clinical significance as well as statistical significance reported?	Yes
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	N/A
9.	Are conclusions supported by results with biases and limitations taken into consideration?		Yes
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	Yes
10.	Is bias due to study's funding or sponsorship unlikely?		Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes