Ergonomic adequacy of university tablet armchairs for male and female: A multigroup item response theory analysis

Abstract

Brazilian university tablet armchairs, often based on international standards, may not suit students well due to anthropometric differences between sexes. This study developed a scale to compare ergonomic adequacy for male and female students, with the potential to significantly impact the future of school furniture. A closed-ended questionnaire containing a four-point Likert scale was administered to 258 students, covering aspects such as seat, backrest, tablet arm, extension, material holder, and general features. The questionnaire's discriminatory capacity and item difficulty were assessed using the multigroup item response theory. The items presented satisfactory values of factor loading (F ​> ​0.3), commonality (h²>0.2), discrimination (a_i>0.7), and difficulty (b_i) ​∈ ​[-4.105; 4.208]. Furthermore, the items cover information in a good region above and below the mean (−4 ​< ​θ ​< ​4) for both genders. The scale presented eight levels ranging from no adequacy (θ ​≤ ​29.99) to maximum adequacy (θ ​≥ ​90.00). Male and female exhibited different response patterns, indicating opportunities for furniture improvement for each gender. For example, female often disagree more strongly with ergonomic characteristics at lower levels than male, particularly regarding seat height and backrest width. Male and female responded differently, suggesting varied adequacy needs even at the same adequacy level. These findings could guide Brazilian manufacturers and regulators in producing school furniture considering students' diverse body dimensions and comfort, quality, and safety perceptions.