A pilot study conducted by the authors found that dementia healthcare professionals frequently reported a lack of confidence when assisting patients with hearing care, attributing their care-related anxiety to limited knowledge about hearing aids [19]; this suggests that comprehensive understanding and knowledge of audiology, including hearing aids, are both vital. Accordingly, the H-GUIDE is largely divided into five chapters based on the current gathered information and the desire to know most frequently reported knowledge of dementia healthcare professionals. Then each chapter is divided into several related subchapters (Copyright registration #C-2022-055436) (Table 1).

The first chapter, Hearing Loss and Dementia, presents a basic introduction to the auditory system, the characteristics of ARHL, and the relationship between hearing loss and dementia. The second chapter, Hearing Screening Tests, incorporates these basic tests (i.e., self-reported hearing questionnaires, understanding of audiograms, pure-tone audiometry, and speech audiometry) to deliver positive and accurate hearing screening and/or diagnosis test methods and their interpretation. The third chapter, Introduction to Hearing Aids, defines hearing aids, their characteristics, the classifications for different hearing losses, and the need for hearing aid adaptation for good user. The fourth chapter, Use of Hearing Aids, offers basic knowledge about the structure and classification of hearing aids. Subchapters discuss how to put on and take off the hearing aid, a description of its power controls and functions, and batteries. We also created video clips (putting on and removing hearing aids) using QR codes and high-resolution written text and videos to deliver the most effective teaching and improve recognition memory for successful learning [20]. The fifth chapter, Maintenance of Hearing Aids, deals with the different functional problems that users can encounter in their daily lives, such as care of their hearing aids, how to use a dehumidifier, how to clean their hearing aids, and how to manage several problems by using effective troubleshooting.

Three experts participated in the review of H-GUIDE. One of these three experts was a professor of nursing and had over 20 years of experience in community care and public health. The other two experts were professors of audiology, who specialized in ARHL and aural rehabilitation for 15 years, respectively.

To confirm the effectiveness of H-GUIDE for healthcare professionals handling dementia and taking into account differences due to regional distribution, a cross-sectional multicenter survey was conducted. In Korea, the term “dementia healthcare professionals” was defined as those healthcare professionals, i.e., clinicians, nurses, social welfare workers, care workers (i.e., care assistants, support workers, and nursing home assistants), and other allied healthcare professionals serving in the LTC facility chosen for the research.

Power calculations were performed using G*Power software (version 3.1.9.7; Heinrich Heine University Düsseldorf) to statistically determine the number of subjects. A significant power calculation resulted in 66 subjects (test group= F test, power=0.95, alpha error probability=0.05). However, since the research design of this study consisted of pre-, post-, and follow-up comparisons with an interval of 2 months between post-test and follow-up, the total number of subjects was 71, considering a dropout rate of 5%–20%.

A total of 286 LTC centers and approximately 3,153 workers were, therefore, identified nationwide [21]. After voluntarily requesting their enrollment and inclusion criteria, such as more than 1 year of work experience and being employed during the research period in this study, 128 workers were initially enrolled, and a total of 71 workers (7 facility managers and 64 healthcare professionals) officially participated in this study using a stratified random sampling method.

All procedures for the current study were approved by the Institutional Review Board of Hallym University (#HIRB-2022-08-02), and all experiments were conducted in compliance with the Declaration of Helsinki and International Conference of Harmonization Guidelines for Good Clinical Practice.

To establish the evidence-based study design, the results of 8 studies on the literature-based education and/or training were summarized and analyzed (Supplementary Table 1 in the online-only Data Supplement). Also, any previous studies similar to this experiment were analyzed to determine and set the most appropriate training time and testing interval for the developed H-GUIDE [26,27]. Considering both the significant previous results and the subjects’ continuous participation in the experiment, we adopted a single-group comparison and multiple time point comparison design. Specifically, a pre-test using the KAP, TAM, and HAKI surveys was conducted to identify the subject’s baseline. After conducting that pre-test, interventions, such as H-GUIDE training, were implemented. The intervention was also designated as being 2 to 3 hours of training over 2 days. All subjects reported on their learning time and the number of repetition trials in the post-test. In that post-test, three surveys included in the pre-test were conducted to compare the effects of H-GUIDE education. To confirm whether the learning effect was maintained, follow-up tests were conducted by the KAP, TAM, and HAKI surveys at two-month intervals after completing the post-test.

All the variables were pre-processed for statistical analysis using SPSS software (Ver. 26; IBM Corp.). An independent t-test was also applied to compare the different test time points (i.e., pre-test, post-test, and follow-up) and quantify the educational effects of the H-GUIDE. Statistical significance was set at p<0.05.

The general characteristics of the participants in the current study are demonstrated in Table 2. The mean age of each group was 39.86 years (standard deviation [SD]: 8.80) for facility managers and 39.72 years (SD: 8.32) for healthcare professionals, respectively. The ethnic or cultural background of the subjects was all Korean (100% for each group).

For job titles, facility managers showed that the nurse was the highest portion (85.71%), followed by the caregiver (14.29%). Similar to facility managers, healthcare professionals demonstrated that nurses were the majority of the participants in the current study (73.44%). Allied healthcare professionals (21.88%), practical nurses (3.13%), and caregivers (1.56%) were followed.

In terms of years of experience, for facility managers, those with 2 to 5 years was the highest group (42.86% for facility managers and 60.94% for healthcare professionals), followed by 2 years or less (28.57%), 5 to 10 years (14.29%), and 10 years or more (14.29%). In the case of healthcare professionals, 2 to 5 years (60.94%) was the largest portion, followed by 5 to 10 years (18.75%), 2 years or less (12.50%), and 10 years or more (7.81%).

The professional qualifications of healthcare professionals were examined to identify the ability to provide practical management for their patients. The results showed that most of the healthcare professionals were university graduates (73.44%), followed by those with college graduation or an equivalent degree (20.31%). Graduate school completion showed the smallest portion (6.25%) among healthcare professionals.

For the distribution of facility locations, Jeju showed 57.14% of participation and Gwangju (28.57%) and Gyeongsangbuk (1.92%) were followed. In contrast, healthcare professionals showed that Gangwon was the highest participated location (17.19%). Ulsan (15.63%) and Jeollanam (14.06%) showed similar participate rates and Gyeonggi (10.94%), Gwangju (7.81%), Gyeongsangnam (7.81%), Busan (6.25%), Jeollabuk (4.69%), Gyeongsangbuk (4.69%), Chungcheonnam (3.13%), Seoul (1.56%), and Incheon (1.56%) were followed.

Two different modalities of the H-GUIDE, namely, a written book and an electronic document (i.e., PDF), were provided to all subjects in the current study to promote their learning in various environments. After the education on the H-GUIDE, 100% of the subjects (n=71) responded to the post-test and follow-up, which was carried out 2 months after the post-test.

At the post-test using three surveys, each subject reported on the education time and repeated education trials. The mean education time was 2.54 hours (SD: 1.68). Also, the dementia healthcare professionals repeated the 2.02 trials on average (SD: 0.71). These results suggested that the healthcare professionals working in the dementia field were aware of the necessity and importance of the H-GUIDE [20].

The results of pre-, post-, and follow-up tests using the KAP survey are depicted in Fig. 1 for the facility manager (Fig. 1A) and dementia healthcare professionals (Fig. 1B).

For the pre-test results, the facility manager showed 2.03 points (SD: 0.66) for knowledge and 3.89 points (SD: 0.08) for attitude. The practice area consisted of a binary scale (i.e., yes-no response) and showed 94.29% of negative responses. That is, the facility managers negatively responded to items, such as the presence of standardized hearing tests in a facility, clinical guidelines and the worker assigned to old adults with hearing loss, audiological training and/or education (i.e., usage and/or maintenance of hearing aids and communication strategy), and counseling of hearing loss given to old adults and/or family members. The healthcare professionals scored 3.25 points (SD: 0.92) for knowledge and 3.20 points (SD: 0.91) for attitude. In the same manner as the facility manager, the healthcare professionals negatively responded to the practice area at 91.15%.

After completing the education and/or learning using the H-GUIDE, a post-test was conducted. The facility managers showed a significant improvement in knowledge (mean=3.29, SD=0.62; t=-6.102, p<0.001), whereas no significant change was observed in attitude (mean=4.03, SD=0.79; t=-0.486, p=0.635). There was no significant change in the result on practice area (94.29% of negative responses). The results for the post-test for healthcare professionals showed improvement for knowledge (mean: 3.39 points, SD: 0.77, t=-6.670, p<0.001), attitude (mean: 3.39 points, SD: 0.87, t=-1.518, p=0.131), and practice (t=0.500, p=0.618). The negative responses for the rate of practice area were 92.22%. These results suggest that there was significant improvement in knowledge area for both the facility manager and healthcare professionals after their education and/or learning the H-GUIDE.

After 2 months of post-testing, a follow-up test was carried out to identify the maintenance of the observed improvements. The results for the facility manager demonstrated that knowledge (mean: 3.17 points, SD: 0.51) and attitude (mean: 4.37 points, SD: 0.60) were maintained (t=0.970, p=0.351) or improved (t=-5.601, p<0.001). Practice area showed a decreased negative response rate (77.14%) and significant improvements compared to the pre-test (t=-2.212, p=0.047) and the post-test (t=-2.212, p=0.047). Similar results were observed for the healthcare professionals with 3.36 points (SD: 0.76) for knowledge and 3.39 points (SD: 0.78) for attitude. The negative response rate of practice area (90.10%) also decreased. Significant improvement was also observed in the knowledge area compared to the pre-test (t=-6.545, p<0.001).

The TAM survey was used to identify the PEOU, PU, and IU. Fig. 2 illustrates the outcome measures of the TAM survey across three time points. The results of a pre-test demonstrated 3.07 points (SD: 0.72) for PEOU, 3.58 points (SD: 0.66) for PU, and 2.49 points (SD: 0.94) for IU.

The post-test results showed 3.75 points (SD: 0.74) for PU (t=-1.941, p=0.054) and 3.39 points (SD: 0.84) for IU (t=-5.859, p<0.001), showing improved results; only IU showed statistical significance. Meanwhile, the PEOU (mean: 2.86 points, SD: 0.86) significantly decreased (t=2.750, p=0.007). These results demonstrated that healthcare professionals serving dementia had difficulty learning but were aware of the importance of the H-GUIDE.

The learning effects through the follow-up test for H-GUIDE showed no statistical differences in all areas of the TAM survey, such as for PEOU (mean: 2.73 points, SD: 0.89, t=0.671, p=0.356), PU (mean: 3.77 points, SD: 0.76, t=-0.537, p=0.592), and IU (mean: 3.45 points, SD: 0.90, t=0.103, p=0.918). These results suggest that both improved (i.e., PU and IU) and decreased areas (i.e., PEOU) were maintained.

The results of the HAKI (Hearing Aid Knowledge Inventory) survey are presented in Fig. 3. In the pre-test, healthcare professionals working with individuals with dementia had a mean score of 21.79 (SD=4.60), corresponding to a percent correct of 62.26%. The post-test showed a significant improvement in hearing aid knowledge (mean=25.15, SD=4.82; t=-4.257, p<0.001). The follow-up test indicated that the improved level of hearing aid knowledge was maintained, with scores remaining significantly higher than those of the pre-test (mean=25.48, SD=4.97; t=-4.593, p<0.001), while no significant difference was observed between the post-test and the follow-up test (t=-0.394, p=0.694).

The present study found that both facility managers and healthcare professionals showed similar improvements in KAP after the H-GUIDE intervention, reflecting existing research that brief educational programs can enhance dementia care competencies [22,28]. While post-intervention knowledge and attitude improved significantly, knowledge retention decreased over time and practice changes remained limited initially [28]; however, delayed improvements in practical application were observed at follow-up, indicating gradual uptake among care professionals [22]. The relationship between knowledge, attitude, and practice supports the information-processing model, emphasizing that behavior change is influenced by both personal knowledge and institutional context.

Further, external factors such as time constraints, attention, and organizational infrastructure constrained outcomes, underscoring the need for structured continuing education and institutional support to facilitate effective hearing care for older adults [12,27,28]. Given that over 86% of LTC residents rely on professional support for hearing aid use and maintenance, these findings highlight the urgent need for continued hearing-related education and institutional cooperation. Hence, both individual-level knowledge and organization-level support systems remain crucial for sustainable hearing care improvement.

The TAM results demonstrated significant post-intervention gains in PU and IU, while PEOU decreased. This pattern supports previous evidence showing that PU and PEOU directly influence IU [29]. The dual-format H-GUIDE (printed and electronic) may have influenced user perception, where PU was identified as a major determinant of IU [30]. Exogenous factors such as subjective norm and image—reflecting the influence of peers, supervisors, and perceived professional status—were also relevant [25,30]. These findings suggest that healthcare professionals are inclined to adopt educational tools they perceive as practically beneficial and socially supported within their professional environment. Overall, the significant improvement in PU and IU indicates that dementia care professionals recognized the H-GUIDE as both relevant and applicable in real-world practice.

H-GUIDE training effectively enhanced hearing aid-related knowledge, with improvements maintained at the two-month follow-up. This parallels earlier research showing that older adults with dementia depend on professional assistance to maximize hearing aid benefits, yet many caregivers lack necessary skills [31,32]. In this study, participants’ pre-test scores reflected only 62.26% accuracy, which substantially improved post-intervention. Similar results were reported by Bennett, et al. [32], where structured education increased confidence and competence in device maintenance and usage. These findings affirm that targeted education promotes greater proficiency, hearing aid adaptation, and motivation for sustained use among professional caregivers [33].

A key limitation of this study is the absence of a control group, as ethical and logistical constraints in LTC facilities made it difficult to recruit non-intervention participants. Consequently, a single-group repeated measures design was used, which allowed examination of within-group changes over time but limited the ability to attribute outcomes solely to the educational intervention. Additional limitations include reliance on self-report and knowledge-based evaluations instead of direct observation due to institutional restrictions and busy clinical environments, and the absence of practical assessment of hearing aid handling. Future studies should incorporate randomized controlled trials and objective performance measures to validate intervention efficacy and better bridge the gap between theoretical knowledge and practical competency among dementia healthcare professionals [20].