SYSTEMATIC LITERATURE REVIEW
Table 2 shows the articles included in the study with the presentation of bibliometric data. It should be noted that the selected studies covered the period of publication between 2005 and 2019, revealing that this is a relatively recent topic. It is noteworthy that there was no delimitation in this review, and even so, 85% of the studies were published within the last ten years.
Table 2
Year | Author | Reference | Title | Study country | Journal |
2005 | Scales Jr., C.D., Jones, P.J., Eisenstein, E.L., Preminger, G.M., Albala, D.M. | [26] | Local cost structures and the economics of robot assisted radical prostatectomy | USA | Journal of Urology |
2008 | Ramiarina, R., Almeida, R.M.V.R., Pereira, W.C.A. | [27] | Hospital costs estimation and prediction as a function of patient and admission characteristics | Brazil | The International Journal of Health Planning and Management |
2010 | Kohan, E., Hazany, S., Roostaeian, J., Allam, K., Head, C., Wald, S., Vyas, R., Bradley, J.P. | [28] | Economic advantages to a distraction decision tree model for management of neonatal upper airway obstruction | USA | Plastic and Reconstructive Surgery |
2011 | Handy Jr., J.R., Denniston, K., Grunkemeier, G.L., Wu, Y.X. | [29] | What is the inpatient cost of hospital complications or death after lobectomy or pneumonectomy? | USA | Annals of Thoracic Surgery |
2011 | Dowsey, M.M., Liew, D., Choong, P.F.M. | [30] | Economic burden of obesity in primary total knee arthroplasty | Australia | Arthritis Care and Research |
2012 | Kamath, A.S., Sarrazin, M.V., Vander Weg, M.W., Cai, X., Cullen, J., Katz, D.A. | [31] | Hospital costs associated with smoking in veterans undergoing general surgery | USA | Journal of the American College of Surgeons |
2013 | Kurichi, J.E., Vogel, W.B., Kwong, P.L., Xie, D., Bates, B.E., Stineman, M.G. | [32] | Factors associated with total inpatient costs and length of stay during surgical hospitalization among veterans who underwent lower extremity amputation | USA | American Journal of Physical Medicine and Rehabilitation |
2014 | McDonald, M.R., Sathiyakumar, V., Apfeld, J.C., Hooe, B., Ehrenfeld, J., Obremskey, W.T., Sethi, M.K. | [33] | Predictive factors of hospital length of stay in patients with operatively treated ankle fractures | USA | Journal of Orthopaedics and Traumatology |
2014 | McCarthy, I.M., Hostin, R.A., Ames, C.P., Kim, H.J., Smith, J.S., Boachie-Adjei, O., Schwab, F.J., Klineberg, E.O., Shaffrey, C.I., Gupta, M.C., Polly, D.W. | [34] | Total hospital costs of surgical treatment for adult spinal deformity: An extended follow-up study | USA | Spine Journal |
2015 | Sözmen, K., Pekel, Ö., Yılmaz, T.S., Şahan, C., Ceylan, A., Güler, E., Korkmaz, E., Ünal, B. | [35] | Determinants of inpatient costs of angina pectoris, myocardial infarction, and heart failure in a university hospital setting in Turkey | Turkey | Anadolu Kardiyoloji Dergisi |
2016 | Vogl, M., Warnecke, G., Haverich, A., Gottlieb, J., Welte, T., Hatz, R., Hunger, M., Leidl, R., Lingner, H., Behr, J., Winter, H., Schramm, R., Zwissler, B., Hagl, C., Strobl, N., Jaeger, C., Preissler, G. | [36] | Lung transplantation in the spotlight: Reasons for high-cost procedures | Germany | Journal of Heart and Lung Transplantation |
2018 | Menendez, M.E., Lawler, S.M., Shaker, J., Bassoff, N.W., Warner, J.J.P., Jawa, A. | [37] | Time-driven activity-based costing to identify patients incurring high inpatient cost for total shoulder arthroplasty | USA | Journal of Bone and Joint Surgery - American Volume |
2019 | Monsivais, D; Morales, M; Day, A; Kim, D; Hoh, B; Blackburn, S | [38] | Cost Analysis of Endovascular Coiling and Surgical Clipping for the Treatment of Ruptured Intracranial Aneurysms | USA | World Neurosurgery |
Regarding authors, it is observed that there was no repetition in different works. This finding may mean that there is no concentration of studies or a reference center of prominence in addressing the topic.
Among the countries in which studies on the subject were conducted, it is noted that there is a high concentration in the United States, with nine researches, equivalent to 69% of the total. At the same time, Brazil, Australia, Turkey, and Germany had one study done in each country.
Regarding journals, it is observed that the studies were published in different journals; therefore, there is no concentration. Most of the articles analyzed were published in medical journals, normally associated with the specialties whose surgical procedures were related. There is a lack of references with application to a greater variety of methods.
Table 3 shows the results of the qualitative analysis of the content of the articles considering the purpose of this literature review. The most relevant result is that no article has proposed a cost calculation model for surgical hospitalizations, revealing that this is a gap in the literature to address this topic that this research comes to fill.
Following the assessment of each article, they were evaluated to identify which ones presented the methodology under which the costs presented were determined. Only eight studies declared the methodology used. Activity-Based Costing (ABC) was observed twice [29, 30], and unit cost [25], micro allocation [27], bottom-up [28], activity-based micro-costing [34], e Time-Driven Activity-Based Costing (TDABC) [35] were applied once each.
The other five works were maintained in this review because, despite not proposing a model for calculating costs and not declaring the methodology used for the costing process, they detailed in some way how the cost calculation was carried out.
Table 3
Qualitative analysis of the articles included in the study
Author | Reference | Proposed cost calculation model? | Is there a declared costing methodology? Which one? | Objective | Number of different surgical procedures |
Scales Jr., C.D., Jones, P.J., Eisenstein, E.L., Preminger, G.M., Albala, D.M. | [26] | No | No | Compare costs between procedures with different techniques | 2 |
Ramiarina, R., Almeida, R.M.V.R., Pereira, W.C.A. | [27] | No | Yes, unit cost | Estimate cost per specialty / clinic and propose a model to analyze the relationship between costs and patient admission characteristics | - |
Kohan, E., Hazany, S., Roostaeian, J., Allam, K., Head, C., Wald, S., Vyas, R., Bradley, J.P. | [28] | No | No | Ascertain the economic advantages of an alternative treatment model compared to conventional treatment | 2 |
Handy Jr., J.R., Denniston, K., Grunkemeier, G.L., Wu, Y.X. | [29] | No | Yes, microallocation | Understand the cost of complications in patients who have undergone thoracic surgery | 2 |
Dowsey, M.M., Liew, D., Choong, P.F.M. | [30] | No | Yes, bottom-up | Estimate obesity-related overhead associated with knee arthroplasty | 1 |
Kamath, A.S., Sarrazin, M.V., Vander Weg, M.W., Cai, X., Cullen, J., Katz, D.A. | [31] | No | Yes, Activity Based Cost (ABC) | Compare costs of surgical hospitalizations between smoking and non-smoking patients | - |
Kurichi, J.E., Vogel, W.B., Kwong, P.L., Xie, D., Bates, B.E., Stineman, M.G. | [32] | No | Yes, Activity Based Cost (ABC) | Investigate factors associated with cost and length of stay | 1 |
McDonald, M.R., Sathiyakumar, V., Apfeld, J.C., Hooe, B., Ehrenfeld, J., Obremskey, W.T., Sethi, M.K. | [33] | No | No | Relate anesthetic assessment score to length of stay and costs | 1 |
McCarthy, I.M., Hostin, R.A., Ames, C.P., Kim, H.J., Smith, J.S., Boachie-Adjei, O., Schwab, F.J., Klineberg, E.O., Shaffrey, C.I., Gupta, M.C., Polly, D.W. | [34] | No | No | Calculate specific procedure cost | 1 |
Sözmen, K., Pekel, Ö., Yılmaz, T.S., Şahan, C., Ceylan, A., Güler, E., Korkmaz, E., Ünal, B. | [35] | No | Yes, bottom-up | Determine cost impact of factors related to cardiovascular diseases | 3 |
Vogl, M., Warnecke, G., Haverich, A., Gottlieb, J., Welte, T., Hatz, R., Hunger, M., Leidl, R., Lingner, H., Behr, J., Winter, H., Schramm, R., Zwissler, B., Hagl, C., Strobl, N., Jaeger, C., Preissler, G. | [36] | No | Yes, activity based micro-costing | Calculate specific procedure cost | 1 |
Menendez, M.E., Lawler, S.M., Shaker, J., Bassoff, N.W., Warner, J.J.P., Jawa, A. | [37] | No | Yes, Time-Driven Activity Based Costing (TDABC) | Calculate specific procedure cost | 1 |
Monsivais, D; Morales, M; Day, A; Kim, D; Hoh, B; Blackburn, S | [38] | No | No | Compare costs between procedures with different techniques | 2 |
It is also possible to analyze in Table 3 that cost studies are generally applied to a few different surgical procedures. This is due to the complexity of the cost determination process and the methodology used, normally linked to the investigation of the records of each patient.
There were variations in the central objectives of the analyzed studies. However, it is noted that identifying the cost of the procedure was a concern of several researchers. Even so, it is observed that the costing process was carried out differently among the different studies, which can be justified by the absence of a reference model.
In the following paragraphs, highlights and gaps observed in the studies included in this review are presented:
Scales et al [26] used the daily hospitalization cost and the fixed cost per procedure in the operating room. They noted that cost is impacted by the volume of procedures and used the hospital cost centers separated in surgical costs and costs of hospitalization. However, in their study, the cost of personnel was established based on the national reimbursement table used in the United States by the MEDICARE health insurance system, the length of stay, duration of surgery (based on other studies), and the variable operating room cost does not depend on the type of surgery.
Ramiarina et al [27] refer to the cost per day and the average length of stay, using data from the Brazilian Unified Health System (SUS) and use the cost center to infer the cost per specialty (clinic). However, the proposed methodology does not allow assuming the cost of surgical procedures individually, just by specialty or clinic.
Kohan et al [28] perform the calculation for each patient, investigating the bills, and multiplying the length of stay by the average cost of the daily hospital. On the other hand, do not present the methodology applied to identify all costs, mainly indirect. Personnel costs were established based on the national MEDICARE reimbursement table.
Handy et al [29] use a computerized cost calculation system and consider direct and indirect costs. In their study, weights were used in combination with monthly volumes to allocate costs, by type of cost. Personnel costs in their study are not included.
Dowsey et al [30] include in their research the cost of all treatment, including readmissions, extracting data from the hospital system for each patient. Also, they organize the presentation of results by cost category.
Kamath et al [31] and Kurichi et al [32] use a decision support system that applies ABC to determine costs at the level of each patient. For Kamath et al [31] intermediate costs are allocated based on the proportion to the final procedure, and other indirect costs are apportioned by weight, such as the department area where the patient is. However, in their study, they do not specify which surgery is being analyzed. Kurichi et al [32] determined which characteristics would be associated with total hospitalization costs and identify which hospitalization costs and length of stay are highly correlated. Although they do not include rehabilitation costs, they do not show how indirect costs were allocated, and they do not show whether personnel costs (eg, doctors) were considered.
McDonald et al [33] report that the average cost of hospital stay (treated as a unit cost) was obtained from the hospital's financial service and that the length of stay was multiplied by the unit cost to define total cost, but does not explain how the average total cost per night was calculated.
McCarthy et al. [34] make use of administrative data and separate costs between general hospital costs and costs in the operating room, but do not explain how the total average cost per hospitalization was calculated and do not include the cost of doctors (surgeons and anesthetists) in their calculation.
Sözmen et al. [35] inform that the data per patient were obtained from the hospital's accounting department and use mean and median to present the values of their study. Costs related to administration, food, cleaning, laundry, water, and electricity generally correlated with length of stay were not considered, and these can have a significant share in total costs.
Vogl et al [36] calculate costs per patient based on hospital accounting system data and define cost centers and calculate average costs for each center. However, they do not show which criterion was used to apportion indirect costs.
Menendez et al [37] used the hospital's software to extract information and have elaborated a flow from the care model to the treatment to assist in the costing process. On the other hand, indirect costs were excluded, as exhaustive modeling and analysis would be necessary, and despite declaring the use of TDABC, in their study, the times were not timed but estimated.
Monsivais et al [38] obtained the cost per patient from the hospital's supply database and accounting system and used the average to present cost results. However, they do not present which criterion was used to apportion indirect costs.
As a conclusion of this review, there is no universally accepted model for determining costs of surgical admissions, there is a wide variation in the methodology applied in studies with a similar purpose, and most cost studies covered only one or a few procedures, which demonstrates the difficulty in carrying out such studies, usually dependent on an investigation full of manual data collection procedures, which makes them difficult to repeat.
However, there are characteristics present in the studies included in this review that can be adopted, such as the use of cost centers, measures of central tendency such as average and median, use of computerized systems for data collection, the definition of criteria for apportionments, in particular, to enable the incorporation of indirect costs, and finally, the inclusion of personnel costs.
The proposed model includes three moments of the perioperative process: preoperative stage, which includes the admission of the patient to the hospital and his admission to the surgical infirmary; operative stage, which includes anesthetic induction, surgery, and anesthetic recovery in the operating room; postoperative hospital stage, with a return to the infirmary or referral to the ICU, until the patient's discharge [39].
The costs related to the preoperative and the postoperative moments are presented as "Hospitalization cost", and those related to the operating room as "Operating room cost". “Personnel costs” are identified separately, as they can be treated independently and thus allow greater comparability between institutions with different hiring models.
Figure 3 presents the model for calculating costs of surgical hospitalizations, which the result is the sum of costs in the operating room, hospitalization and personnel, for each different procedure.
The "Operating room cost" is composed of the sum of the direct unit cost, represented by the median value of the Hospital Medical Supplies and Medicines spent during surgery registered at electronic consumption notes of HIS, and also the indirect cost of the operating rooms of the hospital prorated by the respective number of procedures performed in each of the operating rooms from the hospital.
The “Hospitalization cost” is obtained by adding the daily cost at Inpatient Unit of the Surgical Clinic (UICC) and Intensive Care Unit (ICU), exams performed, and Internal Regulation Center (NIR) costs, prorated based on the average length of stay in the period for each distinct surgical procedure, the proportion of surgical hospitalizations in concerning the total, the proportion of the tests requested for surgical hospitalizations in relation to the total.
The “Personnel cost” is estimated using the same parameters for apportioning the Hospitalization cost, and the frequency of surgical hospitalizations in each operating room is added. Personnel costs are also obtained by absorption in the cost centers but segregated from the Operating room cost and the Hospitalization cost. The reason is that the reference value established in the SUS Table also segregates these values in the form of “professional services”, so it is possible to carry out an independent analysis.
In order to apply the model, the procedures and quantitative of exams performed (frequency) must be identified, as well as the average length of stay at the UICC and ICU, in a given period. Then, the materials and remedies consumed for each different procedure during the surgery must be identified, with the respective values. This step can be performed by reading the information from the consumption notes of materials and medicines filled during the surgery in manual or electronic means at HIS.
Indirect costs were allocated using the absorption costing methodology in which expenses are allocated to cost centers, thus allowing the identification of those relevant to surgical hospitalizations. For the composition of these indirect costs, were accounted the values referring to: Personnel; Hospital Medical Supplies and Medicines used in the infirmary; Patient Removal; Nutrition and Dietetics Service; Clothing; Common Waste Collection; Cleanliness and conservation; Maintenance and Conservation of Real Estate; Maintenance and Conservation of Machines and Equipment; Reception; Surveillance and / or Security; Water and sewage; Data communication; Electricity; and Telecommunications.
For the model, the desirable cost centers are: Surgical Centers (with the exception of materials and medicines, already included in the consumption notes); infirmary, called UICC; ICU; diagnostic support units, responsible for Exams; and technical-administrative unit for hospitalization and discharge of patients, called Internal Regulation Center (NIR).