PAI- Product Aesthetics Inventory
Aesthetics is much more than just "looking good". It is a key factor in the design and success of products, because first impressions count and have a significant influence on how users perceive and interact with a product. Appealing aesthetics can create trust, increase attractiveness and ultimately have a positive influence on purchasing decisions. Despite the enormous investments in the development and optimisation of products, there have been hardly any differentiated and validated tools to objectively evaluate their aesthetics. In order to close this gap, we have developed the Product Aesthetics Inventory (PAI) and its short version PAI-S. Based on three comprehensive studies with over 7,000 respondents, the PAI was comprehensively psychometrically validated. It is now possible to record product aesthetics reliably and in detail. With 32 questions, you can analyse eight different dimensions: Visual aesthetics, controls, brand logo, feedback sounds, operating sounds, haptics, interaction aesthetics and impression. An overall score for product aesthetics can be determined with both the comprehensive PAI and the PAI-S short version comprising just eight questions. Questionnaire templates as well as detailed evaluation and interpretation aids are available online free of charge.
- PAI paper questionnaire: German version
- PAI paper questionnaire: English version
- PAI-S paper questionnaire: German short version
- PAI-S paper questionnaire: English short version
- Online supplement including analysis templates in English and German, analysis scripts (R), codebook and anonymised raw data of study 3
Thielsch, M. T., Forthmann, B., Brau, H., & Eisbach, S. (2024). All that glitters is gold: Development and validation of the Product Aesthetics Inventory (PAI). Psychology of Aesthetics, Creativity, and the Arts, 18(5), 716-736. https://doi.org/10.1037/aca0000494
Ramrath, M., Eisbach, S., Forthmann, B., Brau, H., Thielsch, M.T. (2025). Form is Function! Measuring the Impact of Product Design: Presentation of the Product Aesthetics Inventory (PAI). In: Schrepp, M. (eds) Design, User Experience, and Usability. HCII 2025. Lecture Notes in Computer Science, vol 15795. Springer, Cham. https://doi.org/10.1007/978-3-031-93224-3_27
Thielsch, M. T., Forthmann, B., Brau, H. & Eisbach, S. (2022). Form is function! Measuring the impact of product design in a differentiated way. In: Ludewig, E., Jackstädt, T. & Hinze, J. (Eds.), Mensch und Computer 2022 - Workshopband. Bonn: Gesellschaft für Informatik e.V.. https://10.18420/muc2022-up-269
FAQ
You are welcome to use the PAI or the PAI-S to test your own product! We would be particularly pleased if you could tell us about your experiences afterwards or even provide us with anonymised test data for our benchmarking. In this case, simply contact us at aupsy@uni-wuppertal.de.
Important: If you use the PAI, please always cite us accordingly - i.e. in project reports or publications according to the above citations, in the test itself with a short reference to "Thielsch, Forthmann, Brau & Eisbach (2024)", thank you!
Aesthetics are perceived and evaluated very quickly(cf. Bölte et al., 2017). Accordingly, it makes sense to ask for spontaneous answers in the PAI. It typically only takes a few minutes to answer the PAI, and the short version can even be completed in under two minutes.
When a survey is completed, the analysis of the responses to the PAI begins with the overall mean score and the mean scores for each subscale. These are calculated in such a way that low scores mean a high value on the respective scale. To calculate the mean scores for each scale, the individual scores for each subscale are added together and the resulting sum divided by the number of items in the subscale. The general factor, i.e. the overall mean of the questionnaire, can be calculated by adding all scale scores and dividing by eight - or by dividing the sum of all items by 34. With the PAI-S, the items are added together and the overall mean is calculated by dividing by eight. We recommend interpreting the PAI only at the level of the eight facets and the overall mean, but not at the level of the individual items.
An Excel spreadsheet to help analyse the data is available online (at https://doi.org/10.5281/zenodo.6478042).
The response scale given in the original paper can be inverted to a scale from 1 = strongly disagree to 7 = strongly agree, which can increase its practicality. In addition, the scale can be transformed to a scale from 0-100. This transformation takes place in two steps: Firstly, 1 is subtracted from the original scale value, which changes the scale from 1-7 to 0-6. The result is then multiplied by 100/6, which extends the value range from 0-6 to 0-100. Details, including an R script for calculating the modified response scale, can be found here: doi.org 10.1007/978-3-031-93224-3_27.
English instruction see here: https://doi.org/10.1037/aca0000494 and here: https://doi.org/10.5281/zenodo.6478042
Ideally, you can compare your test value with a reference value, for example with a benchmark or a previous evaluation. For completely new products, we have calculated so-called optimal cut points - if this is not reached, a product is rated as aesthetic. These values can be found in the original paper. We have also created benchmarks so that you can compare your results with those of other products.
Currently in German and English.
Yes, the full 34-item PAI and the PAI-S short scale have excellent reliability, with the decrease in measurement accuracy from the full scale (α = .97) to the short scale (α = .89) being relatively small. All eight subscales of the PAI exhibit good to excellent reliability in the range of .85 to .92 (with a number of items between 3 and 7). The construct validity was confirmed by correlations with other established aesthetic scales, intentions and general judgements. Details can be found in the publications on the PAI presented above.
Aesthetics is one of the central characteristics of a product - and the first thing that is perceived. Aesthetics are therefore very important both for the first impression and for long-term use - or even to differentiate a product from others.
