Document Type : Original Article


1 Health Metrics Research Center, Iranian Institute for Health Sciences Research, ACECR, Tehran, Iran

2 Clinical Cancer Research Center, Milad General Hospital, Tehran, Iran



Background: Overcrowding is an important problem for outpatient services in healthcare facilities. Patient flow analysis (PFA) is a useful method for identifying inefficiencies in and facilitating patient flow.
Objective: PFA was used to estimate patient wait time and determine how different clinical disciplines impact wait times in the studied hospital.
Methods: This cross-sectional study investigated a study population comprised of outpatients who referred to clinics at a general hospital in Tehran, Iran. A total of 3836 samples were selected from different stations. Nonrandomized quota sampling was used, and data was gathered using workflow checklists, the content validity of which was proven by experts and hospital authorities. SPSS statistical software was used for data analysis.
Results: Total patient stay in the outpatient setting was an estimated 77 minutes (without considering para-clinic units and pharmacy). More than 90% of this time was spent waiting. The wait time of patients at the clinic was greater than that at other stations, and it was less at the cash station than at other stations. Wait times varied at different clinics (P value < 0.001) and were correlated with physician delay (P value < 0.001).
Conclusion: The most important result of using PFA in the outpatient setting was managing wait times. This study indicated that a considerable amount of a patient’s total stay in the system was related to waiting for physical examinations. This suggests that the first priority in improving the system should be managing patient wait times for physical examinations.


  1. Hall R, Belson D, Murali P, Dessouky M. Patient Flow: Reducing Delay in Healthcare Delivery. Springer US; 2013. doi:10.1007/978-1-4614-9512-3.
  2. Dixon CA, Punguyire D, Mahabee-Gittens M, Ho M, Lindsell CJ. Patient flow analysis in resource-limited settings: a practical tutorial and case study. Glob Health Sci Pract. 2015;3(1):126-134. doi:10.9745/GHSP-D-14-00121.
  3. Bernstein SL, Aronsky D, Duseja R, et al. The effect of emergency department crowding on clinically oriented outcomes. Acad Emerg Med. 2009;16(1):1-10. doi:10.1111/j.1553-2712.2008.00295.x.
  4. Preyde M, Crawford K, Mullins L. Patients’ satisfaction and wait times at Guelph General Hospital Emergency Department before and after implementation of a process improvement project. CJEM. 2012;14(3):157-168. doi:10.2310/8000.2012.110590.
  5. Harnett MJ, Correll DJ, Hurwitz S, Bader AM, Hepner DL. Improving efficiency and patient satisfaction in a tertiary teaching hospital preoperative clinic. Anesthesiology. 2010;112(1):66-72. doi:10.1097/ALN.0b013e3181c617cb.
  6. Aeenparast A, Maftoon F, Farzadi F, Mohamadi A. Waiting time for first outpatient visit in specialty level: assessing the provider related factors. Arch Iran Med. 2015;18(3):185-188.
  7. Bard JF, Shu Z, Morrice DJ, Wang DE, Poursani R, Leykum L. Improving patient flow at a family health clinic. Health Care Manag Sci. 2016;19(2):170-191. doi:10.1007/s10729-014-9294-y.
  8. Mohebbifar R, Hasanpoor E, Mohseni M, Sokhanvar M, Khosravizadeh O, Mousavi Isfahani H. Outpatient waiting time in health services and teaching hospitals: a case study in Iran. Glob J Health Sci. 2013;6(1):172-180. doi:10.5539/gjhs.v6n1p172.
  9. Mardiah FP, Basri MH. The Analysis of Appointment System to Reduce Outpatient Waiting Time at Indonesia’s Public Hospital. Hum Resour Manag Res. 2013;3(1):27-33.
  10. Armony M, Israelit S, Mandelbaum A, Marmor YN, Tseytlin Y, Yom-Tov GB. On patient flow in hospitals: a data-based queueing-science perspective. Stoch Syst. 2015;5(1):146-194. doi:10.1287/14-SSY153.
  11. Abuhay TM, Krikunov AV, Bolgova EV, Ratova LG, Kovalchuk SV. Simulation of Patient Flow and Load of Departments in a Specialized Medical Center. Procedia Comput Sci. 2016;101:143-151. doi:10.1016/j.procs.2016.11.018.
  12. Rojas E, Munoz-Gama J, Sepúlveda M, Capurro D. Process mining in healthcare: a literature review. J Biomed Inform. 2016;61:224-236. doi:10.1016/j.jbi.2016.04.007.
  13. Miró O, Sánchez M, Espinosa G, Coll-Vinent B, Bragulat E, Millá J. Analysis of patient flow in the emergency department and the effect of an extensive reorganisation. Emerg Med J. 2003;20(2):143-148; discussion 148. doi:10.1136/emj.20.2.143.
  14. Potisek NM, Malone RM, Shilliday BB, et al. Use of patient flow analysis to improve patient visit efficiency by decreasing wait time in a primary care-based disease management programs for anticoagulation and chronic pain: a quality improvement study. BMC Health Serv Res. 2007;7:8. doi:10.1186/1472-6963-7-8.
  15. Thi Thao Nguyen S, Yamamoto E, Thi Ngoc Nguyen M, et al. Waiting time in the outpatient clinic at a national hospital in Vietnam. Nagoya J Med Sci. 2018;80(2):227-239. doi:10.18999/nagjms.80.2.227.
  16. Almeida R, Paterson WG, Craig N, Hookey L. A patient flow analysis: identification of process inefficiencies and workflow metrics at an ambulatory endoscopy unit. Can J Gastroenterol Hepatol. 2016;2016:2574076. doi:10.1155/2016/2574076.
  17. Olwanda E, Shen J, Kahn JG, Bryant-Comstock K, Huchko MJ. Comparison of patient flow and provider efficiency of two delivery strategies for HPV-based cervical cancer screening in Western Kenya: a time and motion study. Glob Health Action. 2018;11(1):1451455. doi:10.1080/16549716.2018.1451455.
  18. Khatibi T, Nejadjafari N. Extraction and comparison of the discharge process in a teaching hospital. In J Hosp Res. 2017;6(1):19-29.
  19. Liang B, Turkcan A, Ceyhan ME, Stuart K. Improvement of chemotherapy patient flow and scheduling in an outpatient oncology clinic. Int J Prod Res. 2015;53(24):7177-7190. doi:10.1080/00207543.2014.988891.
  20. Savage DW, Woolford DG, Weaver B, Wood D. Developing emergency department physician shift schedules optimized to meet patient demand. Cjem. 2015;17(1):3-12. doi:10.2310/8000.2013.131224.
  21. Palmer R, Fulop NJ, Utley M. A systematic literature review of operational research methods for modelling patient flow and outcomes within community healthcare and other settings. Health Syst (Basingstoke). 2018;7(1):29-50. doi:10.1057/s41306-017-0024-9.
  22. Rezai S, Chicarilli DM, Hardy K, et al. Use of patient flow analysis to improve patient access and clinical efficiency by decreasing patient wait time in a tertiary community hospital Ob/Gyn ambulatory women’s clinic: a quality improvement (QI) projectst century. Obstet Gynecol Int J. 2015;3(1):248- 253. doi:10.15406/ogij.2015.03.00071.
  23. Zhao L, Lie B. Modeling and Simulation of Patient Flow in Hospitals for Resource Utilization. Simulation Notes Europe. 2010;20(2):41-50. doi:10.11128/
  24. Koo PH, Nielsen KB, Jang J, Kolker A, Simulation-based patient flow analysis in an endoscopy unit. In: 2010 IEEE Workshop on Health Care Management (WHCM); 18-20 Feb. 20102010: Venice, Italy. doi:10.1109/WHCM.2010.5441266.
  25. Aeenparast A, Pour Reza A. Assessing outpatient’s waiting time and its related factor. Journal of Hospital. 1999;1:21-26. [Persian].
  26. Bahadori M, Teymourzadeh E, Ravangard R, Raadabadi M. Factors affecting the overcrowding in outpatient healthcare. J Educ Health Promot. 2017;6:21. doi:10.4103/2277-9531.204742.
  27. Pandit A, Varma L, Pandit A. Impact of OPD waiting time on patient satisfaction. Int Educ Res J. 2016;2(8):86-90.
  28. Hasanpoor E, Delgoshaie B, Abolghasem Gorji H, Khoshkam M, Jannati A, Sokhanvar M. Surveying the standard of outpatient visit time among general hospitals: a case study in Qazvin. Journal of Hospital. 2015;14(3):75-81. [Persian].
  29. Tai-Seale M, McGuire TG, Zhang W. Time allocation in primary care office visits. Health Serv Res. 2007;42(5):1871-1894. doi:10.1111/j.1475-6773.2006.00689.x.
  30. Smeulers M, Dikmans M, van Vugt M. Well-prepared outpatient visits satisfy patient and physican. BMJ Open Qual. 2019;8(3):e000496. doi:10.1136/bmjoq-2018-000496.
  31. Johannessen KA, Alexandersen N. Improving accessibility for outpatients in specialist clinics: reducing long waiting times and waiting lists with a simple analytic approach. BMC Health Serv Res. 2018;18(1):827. doi:10.1186/s12913-018-3635-3.
  32. Hoseini B. Appointment planning and scheduling in primary care [dissertation]. Newark, NJ: Faculty of New Jersey Institute of Technology, Department of Mechanical and Industrial Engineering; 2017.
  33. Granja C, Almada-Lobo B, Janela F, Seabra J, Mendes A. An optimization based on simulation approach to the patient admission scheduling problem using a linear programing algorithm. J Biomed Inform. 2014;52:427-437. doi:10.1016/j.jbi.2014.08.007.
  34. Luo L, Zhou Y, Han BT, et al. A simulation model for outpatient appointment scheduling with patient unpunctuality. International Journal of Simulation and Process Modelling. 2016;11(3-4):281-291. doi:10.1504/IJSPM.2016.078530.