human 10 medical service Article 7 adult 7 female 7 Humans 6 male 6 middle aged 6 Adult 5 Middle Aged 5 young adult 5 Aged 4 Female 4 Male 4 United States 4 Young Adult 4 aged 4 controlled study 3 health care 3 health care cost 3 major clinical study 3 medical care 3 perception 3 COVID-19 2 Cross-Sectional Studies 2 Health Care Costs 2 Models, Statistical 2 Patient Satisfaction 2 ambulatory care 2 article 2