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Critical insights on the application of the theory of planned behaviour to food handlers' food safety practices.

Foodborne diseases remain a significant public health concern, often linked to unsafe food-handling practices. The Theory of Planned Behaviour (TPB) is widely used to predict and explain food safety behaviours, yet its application in this field has not been systematically and in-depth evaluated. This review evaluated how the TPB has been applied to study food handlers' behaviour, focusing on methodological approaches, use of the TACT (Target, Action, Context, and Time) framework, validity, elicitation studies, and reliability. Seventeen studies were included following a systematic search of four databases (Scopus, Web of Science, Wiley Online Library, and Taylor & Francis Online). Data were extracted on behaviour definition, aim of study, main findings, use of indirect and direct TPB measures, use of elicitation studies, internal consistency, content validation, analytical methods used, and any extensions to the original TPB framework. Key elements related to adherence to core TPB principles and measurement practices were extracted using a Checklist. Most studies used direct measures of TPB constructs, and only a few reported procedures for content validation. Considerable variability was found in the reporting of key measurement and psychometric practices. Five studies fully applied the TACT framework, while nine incorporated additional factors such as knowledge and moral norms. Elicitation studies were conducted in five cases where indirect measures were employed. Analytical approaches were mainly based on multiple linear regression, with limited use of more advanced techniques such as structural equation modeling. Twelve studies reported internal consistency results. Overall, the review highlights opportunities to strengthen methodological practices in future TPB research on food safety. Greater attention to conducting and reporting content validation, full application of the TACT framework, reporting of internal consistency, and consistent inclusion of elicitation studies when using indirect measures may enhance transparency, reinforcing the credibility and trustworthiness of research findings. A major methodological limitation of this review was that screening and data extraction were conducted by a single reviewer and no formal quality or risk-of-bias assessment of the included studies was performed. Despite these limitations, the findings provide practical guidance for the development and validation of TPB-based questionnaires and may support more robust food safety research, interventions, and policy initiatives aimed at improving food handlers' practices.

Humans

Nitrogen sources and concentrations shape algal odor compounds: Key drivers of β-cyclocitral and β-ionone in water bodies of the lower Yangtze River.

Taste and odor (T&O) compounds derived from cyanobacterial blooms pose escalating threats to freshwater security worldwide, yet the drivers of specific T&O metabolites remain poorly constrained. Here, we investigated the dual effects of nitrogen (N) sources and concentrations on the production of β-cyclocitral and β-ionone, two algal-derived T&O compounds, through integrated field surveys (54 sites across lakes and rivers) in the eutrophic lower Yangtze River, China, and laboratory cultivation of typical cyanobacteria (Microcystis aeruginosa and Pseudanabaena cinerea). Our field data revealed that the concentrations of β-cyclocitral and β-ionone in lakes and rivers were not significantly different, but increased with the trophic level index. Redundancy analysis and Mantel analysis showed that Microcystis and Pseudanabaena were potentially dominant contributors to β-cyclocitral and β-ionone in the water column. Structural equation modeling and variation partitioning analysis showed that enhanced nitrate (NO3--N) significantly promoted the production of these compounds. Laboratory experiments demonstrated that inorganic N (NaNO₃) maximized total T&O yields by promoting algal biomass, whereas organic N (urea and glutamic acid) elevated the T&O production per unit biomass by 1.5- to 9.5-fold. Notably, Pseudanabaena exhibited a 2.3-fold higher β-ionone yield than Microcystis, with greater sensitivity to N concentrations. Our study highlights the critical role of nitrogen pollution, both source and concentration, in the production of T&O compounds by phytoplankton and provides reference data for managing T&O issues in rivers and shallow lakes.

Norisoprenoids

Multi-omics reveal microbial functional traits and antifungal metabolites associated with lower Pseudogymnoascus destructans loads in bat cave soils.

White-nose syndrome, caused by Pseudogymnoascus destructans (Pd), is a major fungal disease threatening hibernating bats. Cave soils can serve as environmental reservoirs for Pd, yet the microbial and biochemical mechanisms underlying naturally low Pd burdens in some cave environments remain poorly understood. Here, we integrated soil microbiome profiling, metagenomics, metabolomics, multi-omics network analysis, and in vitro validation to investigate the ecological and functional basis of differential Pd loads in hibernating bat caves in Northeast China. The three caves shared cold, humid, and weakly acidic microenvironments, but differed significantly in electrical conductivity, soil water content, nutrient availability, and extracellular enzyme activities. Soil microbial communities showed significant inter-cave variation in composition, diversity, and niche breadth, with stochastic processes contributing substantially to community assembly. Environmental variables, particularly pH and Pd load, were important predictors of microbial community structure. Functional analyses revealed that the low-Pd Gezi Cave was enriched in genes associated with organic carbon degradation, nitrogen input and retention, and secondary metabolism. Metabolomic profiling further identified cave-specific metabolite signatures, among which Biochanin A, 4-Hydroxybenzaldehyde, Vanillin, and Arachidonic acid were negatively correlated with Pd loads. Integrated pathway and network analyses showed that differential genes and metabolites jointly mapped to secondary metabolite biosynthesis, aminobenzoate degradation, and flavonoid degradation pathways, forming a microbe-metabolite-functional gene coupling network involving key taxa such as Rhodococcus, Pseudorhodoplanes, and Rhodoplanes. In vitro assays confirmed that 4-Hydroxybenzaldehyde, Coumarin, and Vanillin inhibited Pd growth. Structural equation modelling further indicated that environmental heterogeneity was associated with variation in Pd loads through microbial functional attributes and metabolite profiles. These findings suggest that naturally low-Pd cave soils are associated with coordinated environmental filtering, microbial functional specialization, and antifungal metabolite production, providing mechanistic insight into microbial and biochemical constraints on Pd persistence in cave reservoirs.

Animals

Relation of infant feeding practices, cigarette smoke exposure, and group child care to the onset and duration of otitis media with effusion in the first two years of life.

The relation of infant feeding practices, cigarette smoke exposure, and group child care to the onset and duration of otitis media with effusion (OME) was evaluated in a cohort of 698 healthy infants prospectively monitored by tympanometry in the home every 2 to 4 weeks until 2 years of age. Except for an experimental group of children who were offered early tube placement, the study children received conventional care from their personal physician or clinic. We used LISREL, a structural equation modeling procedure (computer software), to explore associations between environmental variables and OME onset and duration while controlling for interrelations among the variables. Supine feeding position and early initiation of group child care were associated with earlier onset of OME. Shorter duration of breast-feeding, increased packs of cigarettes smoked per day in the home, and increased hours per week in group child care were associated with an increase in the amount of time with OME during one or more of the age blocks studied (birth to 6, 6 to 12, 12 to 18, and 12 to 24 months). For a decrease in the amount of time with OME during the first 2 years of life, prolonged breast-feeding and upright feeding position should be encouraged, and cigarette smoke exposure should be minimized. Limiting early child care in large groups might also be advisable.

Breast Feeding

The consumption of tobacco, alcohol, and coffee in Caucasian male twins: a multivariate genetic analysis.

Despite the fact that epidemiologic studies demonstrate a consistent covariation between the use of tobacco, alcohol, and coffee, most previous behavioral genetic-studies have determined the contribution of genetic and environmental influences as if the consumption of these substances occurred independently of each other. In this study, we used multivariate structural equation modeling to determine the genetic and environmental overlap in the observed correlations between tobacco smoking and alcohol and coffee drinking in 173 monozygotic and 183 dizygotic male twin pairs (M age = 59 years; range = 52-66 years) who participated in a follow-up cardiovascular examination of the National Heart, Lung, and Blood Institute's Twin Study. Consistent with hypothesized psychoneurogenetic predispositions for the joint use of these substances, the most parsimonious model fitting these data identified a common genetic latent factor underlying the observed associations between smoking, alcohol, and coffee use in this cohort. This factor, herein called polysubstance use, underscores the role of genetic influence on the clustering of these behaviors in the same individual.

Aged

Proximate determinants of child mortality in Liberia.

The study looks at the effects of maternal sociodemographic characteristics and the quality of the environment on child survival through two intervening variables, breast-feeding and prenatal care. A linear structural equation modelling approach was used to examine infant and child survival based on a weighted sample of 5180 Liberian children aged 0-5 years. The findings confirm previous studies, but also reveal complex relationships of the role of education, maternal age and breast-feeding in enhancing child survival.

Breast Feeding

Concurrent validity of GHQ-28 and PSE as measures of change.

Substantial cross-sectional correlations have been reported between the GHQ and PSE (and CIS) total scores. Although necessary, this is not a sufficient condition for assuming good validity of the GHQ as a severity measure in longitudinal and health care evaluation studies. For this purpose the GHQ should also accurately reflect changes in severity over time. To examine their concurrent validity, GHQ and PSE scores were compared, in a three-wave longitudinal study, among 175 new psychiatric out-patients. Using a longitudinal structural equation model that takes measurement error into account, the strength of both the cross-sectional and longitudinal relationship between GHQ and PSE were estimated. The GHQ performed remarkably well; changes in severity as defined by PSE-ID and PSE total score were clearly reflected by changes in GHQ scores. The revised scoring method of the GHQ proposed by Goodchild and Duncan-Jones did not yield superior results.

Adult

Relation of parental alcoholism to early adolescent substance use: a test of three mediating mechanisms.

The current study assessed 3 hypothesized mediating mechanisms underlying the relation between parental alcoholism and adolescent substance use. Using structural equation modeling, we analyzed data obtained from a large community sample of adolescent children of alcoholics and a demographically matched comparison group. Results suggested that parental alcoholism influenced adolescent substance use through stress and negative affect pathways, through decreased parental monitoring, and through increased temperamental emotionality (which was associated with heightened negative affect). Both negative affect and impaired parental monitoring were associated with adolescents' membership in a peer network that supported drug use behavior. The data did not support a link between parental alcoholism and temperamental sociability.

Adolescent

Relation of media exposure to eating disorder symptomatology: an examination of mediating mechanisms.

Although investigators have postulated that the thin ideal for women espoused in the media is related to the high rates of eating disorders among females, little research has examined the relation between media exposure and eating pathology. This study assessed the relation of media exposure to eating disorder symptoms and tested whether gender-role endorsement, ideal-body stereotype internalization, and body satisfaction mediated this effect. In data from 238 female undergraduates, structural equation modeling revealed a direct effect of media exposure on eating disorder symptoms. Furthermore, mediational linkages were found for gender-role endorsement, ideal body stereotype internalization, and body satisfaction. The results support the assertion that internalization of sociocultural pressures mediate the adverse effects of the thin ideal.

Adult

Alternative representations of war zone stressors: relationships to posttraumatic stress disorder in male and female Vietnam veterans.

Four conceptualizations of war zone stressor experiences were defined: traditional combat, atrocities-abusive violence, perceived threat, and malevolent environment. Items from the National Vietnam Veterans Readjustment Study (NVVRS) were reviewed for content, and stressor indexes were created. Using retrospective self-report data from the NVVRS, intercorrelations among stressor scores and between these scores and measures of posttraumatic stress disorder (PTSD) were computed for all veterans and for men and women separately. Structural equation modeling procedures followed. Results indicated that the four stressor indexes were internally consistent, reasonably distinct from one another, and influenced PTSD differentially. Men scored significantly higher than women on all 4 indexes. Whereas the pattern of relationships among the variables was comparable across genders, there was evidence that one path coefficient in the model differed for men and women.

Combat Disorders

Depression, burnout, and perceptions of control in hospital nurses.

Depression, burnout, and perceived job control (PJC) were assessed in 162 nurses. Depression accounted for over 19% of the variance associated with emotional exhaustion--an index of burnout--and PJC accounted for another 6%. Factor analysis of the scales used to measure depression and burnout documented their discriminant validity. Perceptions of uncontrollability were significantly related to higher levels of depression and burnout. Structural equations modeling suggested that perceived uncontrollability is associated with burnout, which, in turn, is related to depressive affect. Against a criterion of actual job control, non-burned-out subjects overestimated their control, whereas burned-out subjects approached complete agreement with criterion. Despite evidence for a "depressive realism effect," greater perceptual accuracy was not attributable to depression among the more burned-out nurses.

Adult

Peer drug associations and emotional restraint: causes or consequences of adolescents' drug use?

A 3-wave longitudinal design was used to examine the relationships among emotional restraint, peer drug associations, and gateway drug use in a sample of 1,256 middle school students. Structural equation modeling was used to compare 3 models: (a) One model viewed drug use as a consequence of emotional restraint and peer variables; (b) 1 viewed drug use as a cause of restraint and peer variables, and (c) 1 included reciprocal effects. All 3 models fit the data fairly well. However, the reciprocal model fit the data significantly better than either of the others. Within this model, low emotional restraint was significantly related to subsequent increases in gateway drug use among boys. In contrast, peer drug models and peer pressure were not related to subsequent changes in gateway drug use. Changes in peer drug models were, however, predicted by previous levels of gateway drug use.

Adaptation, Psychological

Intimate relationships and depression: is there a causal connection?

The causal pathways that link depression and dissatisfaction in intimate relationships were estimated in 115 patients during the first 12 weeks of treatment with cognitive-behavioral therapy for depression. Depression severity, as measured by the Beck Depression Inventory, was negatively correlated with relationship satisfaction at intake and at 12 weeks. However, structural equation modeling was not consistent with the hypothesis that depression severity has a causal effect on relationship satisfaction levels and suggested that relationship satisfaction may have only a weak reciprocal effect on depression severity. As predicted, married patients were substantially less depressed 12 weeks after the beginning of treatment, when controlling for initial depression severity. Contrary to expectations, marital status predicted improvement even when relationship satisfaction was controlled. Unexpectedly, dysthymia at intake was associated with low relationship satisfaction after 12 weeks, when initial relationship satisfaction was controlled, suggesting that chronic, low-level depression may have a stronger association with interpersonal problems than other forms of depression, such as major depressive episodes. The theoretical and clinical implications of the findings are discussed.

Adolescent

Aging and susceptibility to attitude change.

Two hypotheses about the relation between age and susceptibility to attitude change were tested. The impressionable years hypothesis proposes that individuals are highly susceptible to attitude change during late adolescence and early adulthood and that susceptibility drops precipitously immediately thereafter and remains low throughout the rest of the life cycle. The increasing persistence hypothesis proposes that people become gradually more resistant to change throughout their lives. Structural equation models were applied to data from the 1956-1960, 1972-1976, and 1980 National Election Panel Studies in order to estimate the stability of political attitudes and unreliability in measures of them. The results support the impressionable years hypothesis and disconfirm the increasing persistence hypothesis. A decrease in the over-time consistency of attitude reports among 66- to 83-year-olds was found to be due to increased random measurement error in their reports, not to increased attitude change.

Adolescent

Evidence of differential stability of state and trait anxiety in adults.

This study used Structural Equation Modeling (SEM) to assess the differential longitudinal stabilities of state and trait anxiety. In 1985 and 1987, 227 adult volunteers (ages 22-78) rated themselves on established state and trait questionnaires. In addition, aggregated-state anxiety was measured by self-rated frequency of state anxiety experienced over the previous month. Analysis of split-half subscales from single Trait and State Anxiety scales showed the State Anxiety true score factor to have a significantly lower unstandardized autoregression coefficient (.57 vs. .91), indicating less longitudinal stability. Additional models found longitudinal factor correlations .90, .72, and .66 for Trait, Aggregate-State, and State Anxiety, respectively, further establishing the differential stability of each. There were no significant age differences in longitudinal stability or in within-occasion state-trait factor correlations.

Adult

Intergenerational continuity of parental rejection and depressed affect.

Using survey and observational data from a sample of 451 intact families, this study used structural equation modeling to examine the intergenerational continuity of depressed mood and rejecting parenting. The model partially replicated the intergenerational model of Elder, Caspi, and Downey (1986) that indicates a cyclical transmission process by which parents' personality traits affect parent-child interaction, which, in turn, increases the propensity for developmental problems among offspring. The results indicated a pattern of intergenerational transmission of depressed mood through parental rejection of offspring. Multiple reporters and multiple indicators strengthen previous intergenerational findings by reducing some of the method variance biases that have been problematic in prior studies.

Adolescent

The role of negative affectivity in the association between attributions and marital satisfaction.

Structural equation modeling with latent variables was used to test whether negative affectivity, or the cross-situational tendency to experience and express negative thoughts and feelings, correlates with spouses' attributions for relationship events and accounts for the association between attributions and satisfaction. Eighty married couples completed measures of marital satisfaction, attributions, and negative affectivity. Spouses high in negative affectivity tended to make maladaptive attributions, but spouses' attributions were unrelated to the level of negative affectivity reported by the partner. Attributions and marital satisfaction remained associated among husbands and wives after controlling for negative affectivity. These findings clarify the link between attributions and marital satisfaction and raise the possibility that negative affectivity contributes to the attributions that spouses make for negative events in marriage.

Adaptation, Psychological

Provision and receipt of social support and disregard: what is their impact on the marital life quality of infertile and fertile couples?

A longitudinal study examined perceptions of received and provided social support and disregard among members of 248 infertile and fertile married couples. Correlational and structural equation modeling analyses were conducted. Women's and men's perceptions of the amount of social support they gave to and received from their partner were highly positively related. In contrast, agreement between spouses about the amount of provided support was moderate. Both social support and disregard mediated the relationships between stress and marital quality of life. Overall, highly similar patterns of results were found for members of infertile and fertile couples. These results demonstrate the perceptual element of received support and disregard as well as the importance of considering the provider's perspective.

Adaptation, Psychological