Background: Telemedicine adoption has expanded rapidly in recent years, creating new opportunities for access to care, particularly for frail patients or those with mobility limitations. However, the large-scale deployment of remote healthcare services has highlighted the lack of validated instruments to systematically and multidimensionally assess patients' subjective experience. Patient experience is recognized as a key indicator of quality of care, with direct implications for treatment adherence, appropriate use of digital health technologies, and the effectiveness of organizational care models.

Rationale: No instruments have been specifically validated in Italy to measure patient experience in telemedicine. In response, the Fondazione Policlinico Universitario A. Gemelli - Istituto di Ricovero e Cura a Carattere Scientifico (FPG IRCCS) developed, through a co-design process involving expert patients and healthcare professionals, the Patient Experience in Telehealth questionnaire (PET). The tool was designed to capture not only overall satisfaction, but also relational, informational, and organizational domains, as well as perceived economic and environmental impact.

Objectives: The primary objective is psychometric validation of PET, assessing reliability and validity (construct, convergent, and discriminant). Secondary objectives include evaluating the perceived impact of telemedicine on care organization, patient-borne costs, and the environment, and exploring differences according to sociodemographic variables.

Methods: This cross-sectional observational study will administer PET to at least 200 adult patients who received one or more telemedicine services at FPG IRCCS within the preceding three months. Content validity will be assessed by an expert panel. Descriptive analyses, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and reliability testing will be performed. A subgroup will complete a test-retest assessment after 7-14 days.

Hypothesis: PET is expected to demonstrate satisfactory psychometric properties, discriminate across different levels of patient experience, and capture the perceived organizational, economic, and environmental impacts of telemedicine in healthcare delivery.

Inclusion Criteria:

• Age ≥18 years
• Receipt of at least one telemedicine service at FPG IRCCS
• Provision of informed consent to participate in the study.

Exclusion Criteria:

• Cognitive or linguistic difficulties preventing comprehension of the questionnaire, in the absence of an available caregiver to provide assistance.
• Exclusive use of telemonitoring services or asynchronous reporting, as the survey focuses on synchronous interactions (e.g., video consultation).

The study population will consist of adult patients (≥18 years) who have received at least one telemedicine healthcare service at the Fondazione Policlinico Universitario A. Gemelli IRCCS (FPG IRCCS) across one or more specialist clinical areas. Participants will be consecutively recruited during the predefined data-collection period from among patients who received telemedicine services in the three months preceding study initiation, ensuring a heterogeneous sample with respect to age, sex, clinical condition, and level of digital familiarity.