Determinants of computed tomography and magnetic resonance imaging utilization in Taiwan

Understanding the factors that influence CT utilization for mild traumatic brain injury in a low resource setting - a qualitative study using the Theoretical Domains Framework

Introduction

In low resource settings (LRS), utilization of Computed Tomography scan (CTS) for mild traumatic brain injuries (mTBIs) presents unique challenges and considerations given the limited infrastructure, financial resources, and trained personnel. The Theoretical Domains Framework (TDF) offers a comprehensive theoretical lens to explore factors influencing the decision-making to order CTS for mTBI by imaging referrers (IRs).

Objectives

The primary objective was to explore IRs' beliefs about factors influencing CT utilization in mTBIs using TDF in Uganda.Differences in the factors influencing CTS ordering behavior across specialties, levels of experience, and hospital category were also explored.

Materials and Methods

In-depth semi-structured interviews guided by TDF were conducted among purposively selected IRs from 6 tertiary public and private hospitals with functional CTS services. A thematic analysis was performed with codes and emerging themes developed based on the TDF.

Results

Eleven IRs including medical officers, non-neurosurgeon specialists and neurosurgeons aged on average 42 years (SD+/-12.3 years) participated.Identified factors within skills domain involved IRs' clinical assessment and decision-making abilities, while beliefs about capabilities and consequences encompassed their confidence in diagnostic abilities and perceptions of CTS risks and benefits. The environmental context and resources domain addressed the availability of CT scanners and financial constraints. The knowledge domain elicited IRs' understanding of clinical guidelines and evidence-based practices while social influences considered peer influence and institutional culture. For memory, attention & decision processes domain, IRs adherence to guidelines and intentions to order CT scans were cited.

Conclusion

Using TDF, IRs identified several factors believed to influence decision making to order CTS in mTBI in a LRS. The findings can inform stakeholders to develop targeted strategies and evidence-based interventions to optimize CT utilization in mTBI such as; educational programs, workflow modifications, decision support tools, and infrastructure improvements, among others.

Do We Need Another CT Scanner?—The Pilot Study of the Adoption of an Evolutionary Algorithm to Investment Decision Making in Healthcare

Objectives: The purpose of this study was to assess the feasibility of the adoption of a machine learning (ML) algorithm in support of the investment decisions regarding high cost medical devices based on available clinical and epidemiological evidence. Methods: Following a literature search, the set of epidemiological and clinical need predictors was established. Both the data from The Central Statistical Office and The National Health Fund were used. An evolutionary algorithm (EA) model was developed to obtain the prediction of the need for CT scanners across local counties in Poland (hypothetical scenario). The comparison between the historical allocation and the scenario developed by the EA model based on epidemiological and clinical need predictors was established. Only counties with available CT scanners were included in the study. Results: In total, over 4 million CT scan procedures performed across 130 counties in Poland between 2015 and 2019 were used to develop the EA model. There were 39 cases of agreement between historical data and hypothetical scenarios. In 58 cases, the EA model indicated the need for a lower number of CT scanners than the historical data. A greater number of CT procedures required compared with historical use was predicted for 22 counties. The remaining 11 cases were inconclusive. Conclusions: Machine learning techniques might be successfully applied to support the optimal allocation of limited healthcare resources. Firstly, they enable automatization of health policy making utilising historical, epidemiological, and clinical data. Secondly, they introduce flexibility and transparency thanks to the adoption of ML to investment decisions in the healthcare sector as well.

Geographic distribution and utilisation of CT and MRI services at public hospitals in Myanmar

BACKGROUND

Diagnosis by computed tomography (CT) and magnetic resonance imaging (MRI) is important for patient care. However, the geographic distribution and utilisation of these machines in countries with limited resources, such as Myanmar, have not been sufficiently studied. Therefore, this study aims to identify the geographic distribution and utilisation of CT and MRI services at public hospitals in Myanmar.

METHODS

This nationwide, cross-sectional study was conducted at 43 public hospitals in Myanmar. Data were collected retrospectively using a prepared form from 1st January 2015 to 31st December 2017 at public hospitals in Myanmar. A descriptive analysis was performed to calculate the number of CT and MRI units per million population in each state and region of Myanmar. The distribution of CT and MRI units was assessed using the Lorenz curve and Gini coefficient, which are indicators of inequality in distribution.

RESULTS

In total, 45 CT and 14 MRI units had been installed in public hospitals in Myanmar by 2017. In total, 205,570 CT examinations and 18,981 MRI examinations have been performed within the study period. CT units per million population in 2017 varied from 0.30 in Rakhine State to 3.22 in Kayah State. However, MRI units were available only in public hospitals in five states/regions. The Gini coefficient for CT and MRI was 0.35 and 0.69, respectively. An upward trend in the utilisation rate of CT and MRI was also observed during the study period, especially among patients aged between 36 and 65 years.

CONCLUSIONS

Throughout Myanmar, CT units were more equally distributed than MRI units. CT and MRI units were mostly concentrated in the Yangon and Mandalay Regions, where the population density is higher. The geographic distribution and utilisation rate of CT and MRI units varied among states, regions, and patients' age group. However, the utilisation rates of CT and MRI increased annually in all states and regions during the review period. The Ministry of Health and Sports in Myanmar should consider the utilisation and population coverage of CT and MRI as an important factor when there will be procurement of those medical equipment in the future.

Equity assessment of the distribution of CT and MRI scanners in China: a panel data analysis

Background

Distribution equity assessment of computed tomography (CT) and magnetic resonance imaging (MRI) scanners is an important dimension of access to health technology. However, limited studies on the subject have been done in China. This study aims to reveal the distribution status of CT and MRI scanners and assess their distribution equity of them in China.

Methods

Five provinces with 66 cities from China were selected as the study sites. Descriptive analysis was used for the absolute number and number per million population of CT and MRI scanners in the study sites. Fixed effect model was used to examine the health service factors that were associated with the allocation of CT and MRI scanners. The Gini coefficient and concentration index was used to evaluate the distribution equity of CT and MRI scanners.

Results

The absolute number and number per million population of CT and MRI scanners in five provinces were lower than those of Organization for Economic Co-operation and Development (OECD) countries, but annual growth rates were relatively higher from 2005 or 2006 to 2013. Population, GDP, number of hospitals, number of health professionals, number of hospital beds, number of outpatient visits, and number of inpatient visits all had a positive correlation with the allocation number of CT and MRI scanners. Moreover, the number of health professionals and the number of beds had a much closer correlation than other variables. All the Gini coefficients of CT and MRI had decreased overall. The concentration indices of CT and MRI were all positive and no more than 0.30.

Conclusions

Large gaps in the number of CT and MRI scanners per million population between China and OECD countries emerge, although the growth rate is higher in China. The distribution equity of CT and MRI scanners in China was relatively good from 2005 or 2006 to 2013. The overall distribution equity of CT and MRI scanners also improved during the period. However, consideration attention should be given to the area with large economic disparities.

Associations of County-level Radiologist and Mammography Facility Supply with Screening Mammography Rates in the United States

RATIONALE AND OBJECTIVES

The present study aims to assess associations of Medicare beneficiary screening mammography rates with local mammography facility and radiologist availability.

MATERIALS AND METHODS

Mammography screening rates for Medicare fee-for-service beneficiaries were obtained for US counties using the County Health Rankings data set. County-level certified mammography facility counts were obtained from the United States Food and Drug Administration. County-level mammogram-interpreting radiologist and breast imaging subspecialist counts were determined using Centers for Medicare & Medicaid Services fee-for-service claims files. Spearman correlations and multivariable linear regressions were performed using counties' facility and radiologist counts, as well as counts normalized to counties' Medicare fee-for-service beneficiary volume and land area.

RESULTS

Across 3035 included counties, average screening mammography rates were 60.5% ± 8.2% (range 26%-88%). Correlations between county-level screening rates and total mammography facilities, facilities per 100,000 square mile county area, total mammography-interpreting radiologists, and mammography-interpreting radiologists per 100,000 county-level Medicare beneficiaries were all weak (r = 0.22-0.26). Correlations between county-level screening rates and mammography rates per 100,000 Medicare beneficiaries, total breast imaging subspecialist radiologists, and breast imaging subspecialist radiologists per 100,000 Medicare beneficiaries were all minimal (r = 0.06-0.16). Multivariable analyses overall demonstrated radiologist supply to have a stronger independent effect than facility supply, although effect sizes remained weak for both.

CONCLUSION

Mammography facility and radiologist supply-side factors are only weakly associated with county-level Medicare beneficiary screening mammography rates, and as such, screening mammography may differ from many other health-care services. Although efforts to enhance facility and radiologist supply may be helpful, initiatives to improve screening mammography rates should focus more on demand-side factors, such as patient education and primary care physician education and access.

Evaluation of hospital factors associated with hospital postoperative venous thromboembolism imaging utilisation practices

BACKGROUND

Recent research suggests that hospital rates of postoperative venous thromboembolism (VTE) are subject to surveillance bias: the more hospitals 'look for' VTE, the more VTE they find. However, little is known about what drives variation in hospital VTE imaging rates. We conducted an observational study to examine hospital and market characteristics that were associated with hospital-level rates of postoperative VTE imaging, focusing on hospitals with particularly high rates.

METHODS

For Medicare beneficiaries undergoing 11 major operations (2009-2010) at 2820 hospitals, hospital-level postoperative VTE imaging use rates were calculated. Hospital characteristics associated with hospital VTE imaging use rates were examined including case severity, size, ownership, VTE process measure adherence, accreditations, staffing, malpractice environment, and county market factors. Associations between explanatory variables and VTE imaging rates were assessed using quantile regressions at the 25th, median, 75th and 90th quantiles.

RESULTS

Mean postoperative VTE imaging rates ranged from 85.26 (SD=67.38) per 1000 discharges in the lowest quartile of hospitals ranked by VTE imaging rates to 168.86 (SD=76.70) in the highest quartile. Drivers of high imaging rates at the 90th quantile were high resident-to-bed ratio (coefficient=51.35, p<0.01), Joint Commission accreditation (coefficient=19.05, p<0.01), presence of other hospitals in the same market with high imaging rates (coefficient=15.29, p<0.01), average case severity (coefficient=11.97, p<0.01), local malpractice costs (coefficient=11.29, p<0.01), and market competition (coefficient=11.03, p<0.01).

CONCLUSIONS

Hospital teaching status, resident-to-bed ratio, malpractice environment and local market factors drive hospital postoperative VTE imaging use, suggesting that non-clinical forces predominantly drive hospital VTE imaging practices.

Investigating the utilization of radiological services by physician patients: a population-based cohort study in Taiwan

BACKGROUND

Advances in radiology technology have contributed to a substantial increase in utilization of radiology services. Physicians, who are well educated in medical matters, would be expected to be knowledgeable about prudent or injudicious use of radiological services. The aim of this study was to evaluate differences in the utilization of radiology modalities among physician and non-physician patients.

METHODS

This nationwide population-based cohort study was carried out using data obtained from the Taiwan National Insurance Database from 1997 to 2008. Physicians and comparison controls selected by propensity score matching were enrolled in the current study. The claims data of ambulatory care and inpatient discharge records were used to measure the utilization of various radiology modalities. Utilization rates of each modality were compared between physicians and non-physicians, and odds ratios of the utilization of each radiology modality were measured. Multiple logistic regression analysis was used to examine the predictors of X-ray, MRI, and interventional procedures utilization during the study period.

RESULTS

The utilization of most radiologic services increased among physicians and the comparison group during the observation period. Compared to non-physicians, physicians had significantly higher utilization rates of computed tomography and magnetic resonance imaging (MRI) but lower utilization rates of X-rays, sonography, and interventional procedures. After adjusting for age, gender, major diseases, urbanicity, and residential regions, logistic regression analysis showed that, compared to non-physicians, the physicians used significantly more MRI (odds ratio [OR]: 2.19, 95% confidence interval [CI]: 1.68-2.84, P < 0.001) and significantly less X-rays and interventional procedures (OR: 0.85, 95% CI: 0.72-0.99, P = 0.04 for X-rays and OR: 0.67, 95% CI: 0.54-0.83, P < 0.001 for interventional procedures). Being a physician was a significant predictor of greater usage of MRI and of less usage of X-ray and interventional procedures.

CONCLUSIONS

This study revealed different utilization patterns of X-rays, MRI, and interventional procedures between physician and non-physician patients, even after controlling for such factors as socioeconomic status and major diseases.

Increased risk of subarachnoid hemorrhage in patients with systemic lupus erythematosus: a nationwide population-based study

OBJECTIVE

A relatively common occurrence of spontaneous subarachnoid hemorrhage (SAH) in patients with systemic lupus erythematosus (SLE) has been noted; however, the subsequent studies were conflicting. This nationwide population-based study aimed to evaluate the risk of SAH in patients with SLE.

METHODS

We identified 16,967 SLE patients from the Taiwan National Health Insurance (NHI) database between 2000 and 2006, and compared the incidence rate of SAH with 16,967 randomly selected age- and sex-matched non-SLE subjects. A Cox multivariable proportional hazards model was used to evaluate the risk factors of SAH in the SLE cohort.

RESULTS

The SLE cohort had a higher risk of SAH, with an incidence rate ratio of 4.84 (P < 0.001). Despite a younger age, the mortality rate after SAH was significantly higher in the SLE cohort compared to all of the non-SLE SAH patients identified from the 1 million NHI beneficiaries (60.0% versus 38.9%; P = 0.007). Age (hazard ratio [HR] 1.03, 95% confidence interval [95% CI] 1.01-1.05), platelet transfusion (HR 2.75, 95% CI 1.46-5.17), red blood cell transfusion (HR 7.11, 95% CI 2.81-17.97), and a mean daily steroid dose >10 mg of prednisolone or equivalent (HR 4.36, 95% CI 2.19-8.68) were independent risk factors for the new onset of SAH.

CONCLUSION

This study demonstrated that SAH is a rare but associated complication of SLE with a high mortality rate. Other than age, higher mean daily steroid use and a history of platelet or red blood cell transfusion were associated with the occurrence of SAH in patients with SLE.

Physicians' characteristics associated with repeat use of computed tomography and magnetic resonance imaging

BACKGROUND/PURPOSE

The use and cost of computed tomography (CT) and magnetic resonance imaging (MRI) are both very high. The purpose of this study was to evaluate the relation between physicians' characteristics and the CT and MRI repeated within 90 days, using a nationwide population-based data set from Taiwan's National Health Insurance system.

METHODS

All physicians who ordered CT and MRI examinations in 2004-2005 were identified. We analyzed the total number of CT and MRI scans, the number of repeat scans, and the repeat scan rate, according to physician characteristics (specialty, age, sex, and type of practice hospital). A multivariate logistic regression analysis was performed to explore the adjusted relationship between physician characteristics and their rate of ordering repeat CT and MRI.

RESULTS

A total of 16,307 physicians were responsible for a total of 2,152,292 CT and MRI scans during 2004-2005 in Taiwan. The repeat scans accounted for 21.5% of the total scans. Male physicians and physicians aged 41-50 years ordered more repeat scans. Internal medicine physicians ordered 44.3% of all scans and 50.6% of all repeat scans. Surgeons ordered 40.4% of the total scans and 38.5% of repeat scans. Internal medicine physicians were the most frequent users of CT/MRI scans. Family doctors, obstetricians/gynecologists, and pediatricians ranked last among the specialists. Physicians who practiced in medical centers ordered the most CT/MRI scans.

CONCLUSION

Our study shows that repeat use of CT and MRI scans is related to physicians' characteristics. We recommend that different monitoring standards should be set for CT and MRI repeat use by physicians of different specialties and in hospitals of different accreditation levels.

Utilization patterns of diagnostic imaging across the late life course: A population-based study in Ontario, Canada

Objectives:Due to the aging baby boom population, utilization rates of diagnostic imaging (i.e., X-ray, CT, and MRI scanning) have risen rapidly relative to other health services. The aim of this study is to investigate the utilization patterns of outpatient diagnostic imaging services (X-ray, CT, and MRI) across the late life course (65 years and older).

Methods:A population-based retrospective cohort study was conducted for the period April 1, 2005, to March 31, 2006. All Ontario residents aged 65+ and eligible for government health insurance were included in the analysis.

Results:Utilization of diagnostic imaging followed an inverted U-pattern: increasing with advancing age, peaking in the 80–84 age group for CT scans and in the 70–74 age group for MRI and X-rays, and then declining in the later years. Overall, females received significantly more X-rays than males (p&lt; .01), but males received significantly more CT and MRI scans (p&lt; .01). A small proportion of high-users of radiology services accounted for a large proportion of overall utilization. Finally, our analysis revealed that a disproportionately large proportion of high-users of MRI services were in the highest SES quintile. No SES differences were observed for X-ray or CT scans.

Conclusions:Population aging will lead to increased demand for healthcare services. Utilization of outpatient diagnostic imaging services is associated with age, gender, and SES. Given the increasing demand and the limited resources available, there may be a need for programs to target underserved populations to reduce remediable inequities. Whereas patient-level decisions regarding the use of diagnostic imaging are rightfully determined on the basis of clinical factors, allocation decisions should also be informed by the ethical principles of equity and fairness.

Overuse or underuse of MRI scanners in private radiology centers in Tehran

Objectives:The semiprivate health system in Iran has created an opportunity for unnecessary uses of advanced medical equipments including magnetic resonance imaging (MRI). This study aimed to evaluate the evidence for MRI overuse in private diagnostic imaging centers in Tehran, Iran. The objectives of this study were to determine the frequency of use of MRI scans for different complaints and to explore frequency of normal MRI findings as a function of unnecessary MRI use.

Methods:We conducted a survey among private MRI centers in Tehran, Iran, to study the proportion of MRI scans that may result in significant clinical finding. All MRI reports at a specific point in time at selected MRI centers were reviewed by a physician and the findings were recorded as normal, abnormal, or substantial changes.

Results:Of all the MRI reports, 17.2 percent had resulted in normal findings; 9.8 percent ordered for examination of headache, and 4.8 percent for lower back pain.

Conclusion:Unnecessary MRIs are most likely to result in normal finding; although not all the MRI with normal results could be identified as unnecessary. Negative findings from MRI scans may be reassuring to both clinicians and patients. The proportion of normal findings in MRI scans did not provide evidence of MRI overuse in Iran. The results of this study warrant formation of guidelines for the use of MRIs for headache and low back pain disorders.

Diffusion of magnetic resonance imaging in Iran

OBJECTIVES

The aim of this article is to describe the diffusion of magnetic resonance imaging (MRI) in Iran, including regional variations during the period of 1990 to 2005 and international comparisons.

METHODS

Data on the diffusion of MRI were obtained from the Medical Equipment Office of the Ministry of Health (MOH) and, using self-administered questionnaires, from forty-one universities specializing in medical sciences. Data were gathered from the year of first purchase up to mid-2005. Information for international comparisons was obtained from the Organization for Economic Cooperation and Development health data of 2006.

RESULTS

Iran purchased its first MRI unit in 1990. Since then, the number of MRI units has increased remarkably. The diffusion curve of MRI in Iran follows an S-shaped curve with a very slow speed in the period of 1991-95. Accelerated adoption occurred later coinciding with a significant influence from the private sector, especially from 1999. Iran had ninety-three MRI units in 2005, and the number of MRI units per million in the population was 1.36.

CONCLUSIONS

The number of MRI units in provinces is not in direct proportion to the number of their inhabitants. Rational adoption and equitable diffusion of MRI may require the MOH and regulatory bodies to improve their ability in health technology assessment and integrate it into the policy making regarding adoption, diffusion, and utilization of health technologies.

Applying the variety reduction principle to management of ancillary services

BACKGROUND

As central diagnostic facilities, computer tomography (CT) scans appear to be bottlenecks in many patient-care processes. This study describes a case study concerning redesign of a CT scan department in the Academic Medical Center in Amsterdam, the Netherlands.

PURPOSES

The aim was to decrease access time for the CT-scan and simultaneously increase utilization level.

METHODOLOGY/APPROACH

An important cause of relatively low-capacity utilization is variability in the time needed for the scanning process. We performed a qualitative and quantitative analysis of current processes; identified bottlenecks and selected interventions with the greatest expected reduction of variability in flow time.

FINDINGS

The most promising and most feasible opportunity appeared to be to reallocate the insertion of intravenous access lines to a preparation room. The time needed for this activity was very hard to predict and needed a lot of slack in the lead time for appointments. By removing it from the CT room, lead time could be reduced by 5 minutes. The intervention resulted in a decrease of access time from 21 days to less than 5 days, and an increase of the utilization rate from 44% to 51%. This contributed directly to patient service and indirectly to cost reduction.

PRACTICE IMPLICATIONS

Our strategy is applicable in every appointment-based hospital facility with variation in the length of time of the process. It allows to simultaneously reduce costs and improve service for the patient.