Examination of State of the Science of Interventions Designed to Increase Farmers' Use of Hearing Protection Devices.

Abstract

Among published interventions to increase farmers’ hearing protection device (HPD) use several methodological issues are of concern: use of theory, concepts, reliability of measures of self-report, and gender-related differences in predictors of HPD use. Three papers were prepared to better understand use of HPDs among this group of workers and guide subsequent interventions: (a) a critical review of theory implementation in HPD use interventions among farmers, (b) a literature review and examination of the evidence of reliability of self-report as a measurement method, and (c) an examination of gender-related differences in predictors of HPD use among farm operators. Theory examination identified five interventions and six theories (health belief model, transtheoretical model of change, health promotion model, social cognitive theory, PRECEDE-PROCEED, and theory of self-efficacy). While the studies employed health behavior theories to varying degrees, all intervention resulted in increased HPD use. Kappa, correlations, sensitivity/specificity, positive/negative predictive validity, correlations, and logistic regression were used to assess concordance between self-report and non self-report methods. Kappa scores ranged from .01 to .89; sensitivity/specificity scores were 92% and 61% respectively; Pearson’s r, Spearman’s rho, and Kendall tau-b were .89, .84, and .69 respectively; and odds ratios ranged from 1.4 to 19.42. Concordance increased with use of daily activity cards, short time intervals between performance of the behavior and reporting, and limiting recall efforts to five days. The Farmers’ Predictors of Hearing Protection Device Use Model was used to examine gender-related differences in predictors of HPD use. Logistic regression identified different predictors for men (interpersonal support [OR = 2.00, p = .01], situational influences [OR = 1.29, p = .02], barriers [OR = .57, p < .001) and women (self-efficacy [ OR = 2.26, p < .001], value [OR = 1.49, p = .04]). Implications for future research to promote the use of HPDs among farmers include further testing of the Farmers’ Predictors of Hearing Protection Device Model, and revision and successive testing of self-efficacy and interpersonal influences scales. Interventionists seeking to increase HPD use should consider tailoring interventions to the unique gender-specific predictors of farmer men and women.