Smartphone Addiction, Posture and Breathing Control in University Students

This cross-sectional observational study will be conducted between April and September 2026 in healthy university students aged 18-35 years.

Following written informed consent, participants will complete a sociodemographic form including age, sex, body mass index, smoking status, and daily smartphone usage duration.

Smartphone addiction levels will be evaluated using the Smartphone Addiction Scale-Short Form (SAS-SV). Breathing control and dysfunctional breathing symptoms will be assessed using the Self Evaluation of Breathing Questionnaire (SEBQ). Postural assessment will be performed using the New York Posture Rating Chart (NYPRC).

Participants will additionally be categorized according to smartphone addiction status using validated cutoff values for the SAS-SV. Postural status will also be categorized according to NYPRC scores.

Binary logistic regression analysis will be performed to determine whether smartphone addiction is an independent predictor of postural problems. Odds ratios (OR) and 95% confidence intervals (CI) will be reported. Multiple linear regression analysis will additionally be used to examine the relationship between smartphone addiction, posture scores, and breathing control scores while adjusting for potential confounding factors such as age, sex, body mass index, smoking status, and smartphone usage duration.

The study aims to provide evidence regarding the musculoskeletal and respiratory consequences of excessive smartphone use in young adults.

• Observational Assessment (Other): Participants will complete questionnaires assessing smartphone addiction, physical activity level, and breathing control. Postural assessment will be performed using the New York Posture Rating Chart. The study will investigate the association between smartphone addiction, postural problems, and breathing control in university students.

Primary outcomes

• Presence of postural problems [baseline]: Posture will be evaluated using the New York Posture Rating Chart (NYPRC). Participants will be categorized according to posture status. Lower scores indicate poorer posture.

Secondary outcomes

• Smartphone addiction severity [Baseline]: Smartphone addiction severity will be assessed using the Smartphone Addiction Scale-Short Form (SAS-SV). Higher scores indicate greater smartphone addiction.
• Breathing control [baseline]: Breathing control and dysfunctional breathing symptoms will be evaluated using the Self Evaluation of Breathing Questionnaire (SEBQ). Higher scores indicate greater dysfunctional breathing symptoms.

Sex: All, ages: 18 Years to 35 Years, accepts healthy volunteers

Inclusion Criteria:

* Age between 18 and 35 years
* Smartphone user
* Ability to stand independently
* Ability to perform activities of daily living independently
* Ability to understand assessment instructions
* Voluntary participation with signed informed consent

Exclusion Criteria:

* • History of fracture

  * Cardiovascular disease
  * Pulmonary disease
  * Neurological or orthopedic disorders affecting posture or breathing
  * Inability to understand instructions

• EMEL METE, Principal investigator, Istanbul Medeniyet University