The instrument at the center of the study is the Pica, ARFID and Rumination Disorder Interview–ARFID Questionnaire, abbreviated as PARDI-AR-Q. It grew out of the PARDI, a structured clinician interview developed by an international team that includes Rachel Bryant-Waugh of King’s College London and the South London and Maudsley NHS Foundation Trust, one of the co-authors of the new paper. The questionnaire version condenses that interview into a self-report format, asking respondents about sensory-based avoidance of food, lack of interest in eating or appetite, fear of aversive consequences of eating, and the impact of eating problems on everyday functioning. Because ARFID presentations differ so markedly from person to person, capturing these distinct dimensions separately is critical. A person who avoids fruit because of its texture needs a different clinical conversation from someone who eats reluctantly because they fear vomiting, and a good screening tool must be able to distinguish between them.

Translating a psychological questionnaire is far more involved than swapping words between languages. Concepts such as food neophobia, sensory sensitivity, and appetite must resonate with the everyday vocabulary of the target population, and the response scales must behave in the same way statistically. To establish whether the Turkish PARDI-AR-Q met these standards, a research team led by Makbule Esen Öksüzoğlu of Kastamonu University, together with colleagues from several Turkish hospitals and universities, recruited 1,343 university students aged 18 to 40 from three Turkish universities. The sample was 53.4 percent female, with a mean age of 23.6 years. Participants completed the Turkish PARDI-AR-Q alongside a battery of comparison measures: the Nine-Item ARFID Screen, known as NIAS, the Food Neophobia Scale, the short form of the Eating Disorder Examination Questionnaire, and the Depression Anxiety Stress Scale-21. A subset of 138 participants filled out the PARDI-AR-Q a second time roughly four weeks later, allowing the researchers to test whether scores remained stable over time.

The statistical workup was thorough. The team examined internal consistency, the degree to which items within a scale measure the same underlying construct; test–retest reliability, the stability of scores across weeks; exploratory and confirmatory factor analyses, which test whether the questionnaire’s structure matches the theoretical dimensions of ARFID; measurement invariance across sex, age, ARFID-risk status, and weight status; and both convergent and criterion-referenced validity. Each of these analyses answers a different question about the instrument, and together they provide a comprehensive portrait of how the Turkish version behaves in practice. The study received ethics approval from Uşak University and was conducted in accordance with the Declaration of Helsinki, with written informed consent from all participants.

The headline finding is that the Turkish PARDI-AR-Q performed remarkably well. Exploratory factor analysis supported a four-factor structure mirroring the intended dimensions of the instrument, and confirmatory factor analysis showed excellent fit for a correlated four-factor model, with a comparative fit index of 0.990, a Tucker-Lewis index of 0.985, a root mean square error of approximation of 0.049, and a standardized root mean square residual of just 0.017. For readers unfamiliar with these statistics, values close to 1.0 on the first two indices and low values on the latter two indicate that the observed data align almost perfectly with the proposed model. In plain terms, the questionnaire measures four distinct but related facets of ARFID exactly as designed, and it does so in Turkish as cleanly as psychometricians could hope.

Reliability figures were equally impressive. Internal consistency, measured by Cronbach’s alpha, reached 0.95 for the total score, which is excellent, and ranged from 0.86 to 0.92 across the subscales, spanning good to excellent. The four-week test–retest reliability, expressed as intraclass correlation coefficients, fell between 0.921 and 0.947, meaning that a person’s scores changed very little over a month in the absence of any intervention. This stability matters enormously for research: if a screening tool gives wildly different results from one month to the next, it cannot be used to track symptoms or evaluate treatment. The Turkish PARDI-AR-Q passes that test with room to spare.

Validity evidence came from several directions. The PARDI-AR-Q subscales correlated most strongly with the corresponding subscales of the NIAS, with correlation coefficients ranging from 0.663 to 0.760, exactly the pattern expected if both instruments tap the same constructs. Participants who scored above the established NIAS cut-off for ARFID risk scored significantly higher on the PARDI-AR-Q, providing criterion-referenced support. The researchers also demonstrated scalar measurement invariance across sex, age group, ARFID-risk status, and weight status, which means the questionnaire functions comparably for women and men and for younger and older adults, allowing meaningful score comparisons across these groups. On the descriptive side, endorsement of diagnostic and risk-related items was generally low to moderate: 19.8 percent of participants reported perceiving an eating problem themselves, 18.8 percent said a professional had identified a nutritional deficiency, and 17.9 percent reported that others had noticed an eating problem. These figures suggest that eating-related concerns are far from rare in young adult populations, even if few meet full diagnostic criteria.

Why does this matter beyond Turkey? Psychometric validation studies can seem dry, but they are the quiet infrastructure of mental health science. Without validated tools in local languages, entire populations are effectively invisible to epidemiological research, and clinicians must rely on informal judgment or instruments that were never tested for their patients. ARFID in particular has been under-recognized in adults, with much of the literature focused on children and adolescents. The new study is explicitly the first to validate the PARDI-AR-Q outside English-speaking populations, making the Turkish version a template for adaptations elsewhere. The authors note that the questionnaire can now serve as a short, practical screening instrument for Turkish-speaking adults who may be experiencing ARFID symptoms and who might benefit from further assessment or support, opening the door to prevalence studies and clinical trials in a population of more than 80 million people.

The researchers are candid about the limits of their work. The sample consisted entirely of university students, a group that is young, educated, and not representative of the general adult population, let alone of clinical populations. Future studies, they write, should test the questionnaire in people with diagnosed eating disorders and in more diverse groups, including adults outside higher education. A screening tool validated in students may behave differently in older adults, in people with chronic medical conditions, or in psychiatric inpatients. There is also the inherent limitation of self-report: ARFID can involve limited insight, and some individuals may underreport symptoms, which is why the questionnaire is positioned as a screening and research tool rather than a substitute for a full clinical interview such as the original PARDI.

Even with those caveats, the study represents a meaningful step forward for a disorder that has struggled for recognition. ARFID is not picky eating, and it is not a phase that people simply grow out of; it is a condition that can compromise nutrition, growth, and quality of life across the lifespan. Giving clinicians and researchers in Turkey a rigorously validated, quick-to-administer measure of its core symptoms makes it possible to find the people who have been suffering quietly, often mislabeled as merely fussy or anxious around food. As awareness of ARFID grows worldwide, studies like this one quietly ensure that the science of measurement keeps pace, so that no one’s eating difficulties go unseen simply because of the language they speak.

Subject of Research: Validation of the Turkish PARDI-AR-Q questionnaire for assessing ARFID symptoms in adults

Article Title: Validity and reliability of the pica, ARFID and rumination disorder interview- ARFID questionnaire (PARDI-AR-Q) in Turkish adults

Article References: Esen Öksüzoğlu, M., Günal Okumuş, H., Kaşak, M., Çelik, Y. S., Öğütlü, H., & Bryant-Waugh, R. (2026). Validity and reliability of the pica, ARFID and rumination disorder interview- ARFID questionnaire (PARDI-AR-Q) in Turkish adults. Journal of Eating Disorders. https://doi.org/10.1186/s40337-026-01750-3

Image Credits: AI Generated

DOI: 10.1186/s40337-026-01750-3

Keywords: ARFID, PARDI-AR-Q, eating disorders, psychometric validation, questionnaire, Turkish adults, test-retest reliability, factor analysis, screening tool, food neophobia, mental health assessment, Validity