Fig. 2

A-D Association between smartphone use among university students based upon hours of phone use/day (M ± SD) (A), biological change in MSD biomarkers (B), oxidative stress (C), and correlation of MSD markers with neck and hand pain in addicted and healthy control participants (D). SAS: Smartphone Addiction Scale; NDI: Neck Disability Index; CHDQ: Cornell Hand Discomfort Questionnaire; VAS: Visual Analogue Scale; TIMP-1/TIMP-2: metallopeptidase inhibitor 1/2 (a tissue inhibitor of metalloproteinase); MDA: malondialdehyde; TAC: total antioxidant capacity; TG: triglycerides. 5-HT: 5-hydroxytryptamine (serotonin). ^ap < 0.05, ^bp < 0.01, ^cp < 0.001