These measures are comprised of over 700 unique items appropriate for use with adults aged 18 and over, and more than 130 items appropriate for children ages 8-18. Most FACIT items have demonstrated face and content validity, and were created with direct input from patients and expert clinicians. Many items have also been translated into nearly 80 languages (reaching over 100 countries) using a standardized, rigorous translation methodology and tested for comprehension by native speakers. All items in the FACIT Searchable library were created with direct input from patients and expert clinicians, and tested for comprehension by native speakers of the languages into which each item has been translated.

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Until 2017, people used these items via static FACIT questionnaires in a fixed, validated format. Now, with the introduction of the FACIT Searchable Library, one can create a custom form using the site’s Build-a-PRO function and include only those FACIT items most relevant to one’s study or purpose. While doing so does not instantly “validate” the custom composition, it does create an opportunity to select specific items relevant to the research question at hand, using content valid items that have undergone careful translation into other languages. It also allows for the opportunity to pursue validation of the assembled set of questions using standard questionnaire validation practice.

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Two recent trends have led us to provide this new approach:

One is the introduction of item response theory (IRT) into health measurement. One of the guiding principles of IRT measurement is the basic ‘fungibility’ of items measuring the same underlying concept, or domain. In an IRT-calibrated item bank, one can “pick-and choose” items from that bank, according to their content relevance in a given setting. The score obtained is generalizable to other studies or samples that may have used a different set of items from the same bank. Given this, the introduction of IRT into health measurement has led to the question of whether or not more classically-developed measurement systems such as FACIT could consider the value of customized individual item selection. Some FACIT items have become incorporated into or linked with national item banks such as PROMIS and Neuro-QoL, and these could indeed be scored on those national metrics. However, most FACIT items have not been incorporated or linked to existing IRT item banks and would therefore not be able to produce interpretable scores beyond the single item raw score, which is the starting point for most custom forms.

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The second trend leading to this new approach has been increasing pressure from government and private sectors, including patient advocates, to ask only those questions that are directly relevant to the hypothesis of a given study or treatment comparison. This pressure has been growing for several years, culminating in the release of the National Cancer Institute’s Patient Reported Outcome Common Terminology Criteria for Adverse Events (PRO-CTCAE), which is a set of 124 items that query 78 symptom terms from the larger (clinician-rated) CTCAE v4.0. The FACIT Searchable Library covers all of the PRO-CTCAE major categories, maps to 55 of its 78 symptom terms, and addresses several other disease symptoms and treatment adverse events. Similar to how the PRO-CTCAE is deployed, any user could sample questions from the FACIT Searchable Library and evaluate, in descriptive fashion, how one treatment compared to another, on an item-by-item basis.