Between-Hospital and Between-Physician Variation in Outcomes and Costs in High- and Low-Complex Surgery: A Nationwide Multilevel Analysis.

OBJECTIVES: Clinicians and policy makers are increasingly exploring strategies to reduce unwarranted variation in outcomes and costs. Adequately accounting for case mix and better insight into the levels at which variation exists is crucial for such strategies. This nationwide study investigates variation in surgical outcomes and costs at the level of hospitals and individual physicians and evaluates whether these can be reliably compared on performance. METHODS: Variation was analyzed using 92 330 patient records collected from 62 Dutch hospitals who underwent surgery for colorectal cancer (n = 6640), urinary bladder cancer (n = 14 030), myocardial infarction (n = 31 870), or knee osteoarthritis (n = 39 790) in the period 2018 to 2019. Multilevel regression modeling with and without case-mix adjustment was used to partition variation in between-hospital and between-physician components for in-hospital mortality, intensive care unit admission, length of stay, 30-day readmission, 30-day reintervention, and in-hospital costs. Reliability was calculated for each treatment-outcome combination at both levels. RESULTS: Across outcomes, hospital-level variation relative to total variation ranged between ≤ 1% and 15%, and given the high caseloads, this typically yielded high reliability (> 0.9). In contrast, physician-level variation components were typically ≤ 1%, with limited opportunities to make reliable comparisons. The impact of case-mix adjustment was limited, but nonnegligible. CONCLUSIONS: It is not typically possible to make reliable comparisons among physicians due to limited partitioned variation and low caseloads. Nevertheless, for hospitals, the opposite often holds. Although variation-reduction efforts directed at hospitals are thus more likely to be successful, this should be approached cautiously, partly because level-specific variation and the impact of case mix vary considerably across treatments and outcomes.

Practice pattern variation: treatment of pelvic organ prolapse in The Netherlands.

INTRODUCTION AND HYPOTHESIS: Great variety in clinical management of pelvic organ prolapse (POP) has been described over the last years. Practice pattern variation (PPV) reflects differences in care that cannot be explained by the underlying condition. We aim to explore whether PPV in management of POP in The Netherlands has changed between 2011 and 2017. METHODS: We conducted a multicenter cohort study, using prospective routinely collected benchmark data from LOGEX, a healthcare analytics company (Amsterdam, The Netherlands). Data of patients with a diagnosis POP from 50 hospitals (16 teaching and 34 non-teaching hospitals) were collected for the years 2011 and 2017. All treatments were categorized into three groups: conservative treatment, uterus-preserving or uterus-removing surgery. Using meta-analysis, we evaluated whether the proportions of conducted treatments changed over time and estimated the between-center variation (Cochran's Q), reflecting the PPV in 2011 and 2017. This variation was analyzed using F-tests. RESULTS: Compared to 2011, referral for POP in 2017 decreased by 16.2% (-4505 patients), and the percentage of hysterectomies decreased by 33.6% (p < 0.0001). The PPV of POP surgery decreased significantly by 47.2% (p = 0.0137) and of hysterectomies by 41.5% (p = 0.0316). CONCLUSIONS: We found a decline in PPV for POP surgery between 2011 and 2017. Furthermore, the number of surgical interventions decreased, which was mostly due to a decline of hysterectomies. This indicates a shift toward more conservative therapy and uterus preservation. A further reduction of PPV would be beneficial for the quality of health care.

Regional and hospital variation in commonly performed paediatric otolaryngology procedures in the Netherlands: a population-based study of healthcare utilisation between 2016 and 2019.

OBJECTIVE: In the past few decades, there has been an increase in high-quality studies providing evidence on the effectiveness of commonly performed procedures in paediatric otolaryngology. We believe that now is the time to re-evaluate the care process. We aimed to analyse (1) the regional variation in incidence and referrals of adenoidectomies, tonsillectomies and ventilation tube insertions in children in the Netherlands between 2016 and 2019, (2) whether regional surgical rates, referral rates and in-hospital surgical rates were associated with one another, and (3) the hospital variation in healthcare costs, which indicates the utilisation of resources. DESIGN: Repeated cross-sectional analysis. SETTING: Four neighbouring Dutch provinces comprising 2.8 million inhabitants and 14 hospitals. PARTICIPANTS: Children aged 0-15 years. OUTCOME MEASURES: We analysed variation in regional surgical rates and referral rates per 1000 inhabitants and in-hospital surgical rates per 1000 clinic visitors, adjusted for age and socioeconomic status. Furthermore, the relationships between referral rates, regional surgical rates and in-hospital surgical rates were estimated. Lastly, variation in resource utilisation between hospitals was estimated. RESULTS: Adenoidectomy rates differed sixfold between regions. Twofold differences were observed for adenotonsillectomy rates, ventilation tube insertion rates and referral rates. Referral rates were negatively associated with in-hospital surgical rates for adenotonsillectomies, but not for adenoidectomies and ventilation tube insertions. In-hospital surgical rates were positively associated with regional rates for adenoidectomies and adenotonsillectomies. Significant variation between hospitals was observed in costs for all resources. CONCLUSIONS: We observed low variation in tonsillectomies and ventilation tube insertion and high variation in adenoidectomies. Indications for a tonsillectomy and ventilation tube insertion are well defined in Dutch guidelines, whereas this is not the case for an adenoidectomy. Lack of agreement on indications can be expected and high-quality effectiveness research is required to improve evidence-based guidelines on this topic.

Changes in healthcare utilisation for paediatric tonsillectomy and adenoidectomy in the Netherlands: a population-based study.

OBJECTIVES: Tonsillectomy and adenoidectomy in children are controversial subjects with large regional variation in surgical rates, partly explained by cultural differences and lack of high-quality evidence on indications for surgery. A quality of care cycle was executed on this topic in the Netherlands. The objective of this study was to estimate changes in healthcare utilisation for paediatric tonsil surgery in the Netherlands. METHODS: Population-based data on tonsillectomies and adenoidectomies in children up to age 10 were retrieved retrospectively from Dutch administrative databases between 2005 and 2018. A change point analysis was performed to detect the most pivotal change point in surgical rates. We performed univariate analyses to compare surgical patients' characteristics before and after the pivotalpoint . Impact on healthcare budget and societal costs were estimated using current prices and data from cost-effectiveness analyses. RESULTS: The annual number of adenotonsillectomies reduced by 10 952 procedures (-39%; from 129 per 10 000 children to 87 per 10 000 children) between 2005 and 2018, and the number of adenoidectomies by 14 757 procedures (-49%; from 138 per 10 000 children to 78 per 10 000 children). The most pivotal change point was observed around 2012, accompanied by small changes in patient selection for surgery before and after 2012. An estimated €5.3 million per year was saved on the healthcare budget and €10.4 million per year on societal costs. CONCLUSION: The quality of care cycle resulted in fewer operations, with a concomitant reduction of costs. We suggest that part of these savings be invested in new research to maintain the quality of care cycle.

Is Textbook Outcome a valuable composite measure for short-term outcomes of gastrointestinal treatments in the Netherlands using hospital information system data? A retrospective cohort study.

OBJECTIVE: To develop a feasible model for monitoring short-term outcome of clinical care trajectories for hospitals in the Netherlands using data obtained from hospital information systems for identifying hospital variation. STUDY DESIGN: Retrospective analysis of collected data from hospital information systems combined with clinical indicator definitions to define and compare short-term outcomes for three gastrointestinal pathways using the concept of Textbook Outcome. SETTING: 62 Dutch hospitals. PARTICIPANTS: 45 848 unique gastrointestinal patients discharged in 2015. MAIN OUTCOME MEASURE: A broad range of clinical outcomes including length of stay, reintervention, readmission and doctor-patient counselling. RESULTS: Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) for gallstone disease (n=4369), colonoscopy for inflammatory bowel disease (IBD; n=19 330) and colonoscopy for colorectal cancer screening (n=22 149) were submitted to five suitable clinical indicators per treatment. The percentage of all patients who met all five criteria was 54%±9% (SD) for ERCP treatment. For IBD this was 47%±7% of the patients, and for colon cancer screening this number was 85%±14%. CONCLUSION: This study shows that reusing data obtained from hospital information systems combined with clinical indicator definitions can be used to express short-term outcomes using the concept of Textbook Outcome without any excess registration. This information can provide meaningful insight into the clinical care trajectory on the level of individual patient care. Furthermore, this concept can be applied to many clinical trajectories within gastroenterology and beyond for monitoring and improving the clinical pathway and outcome for patients.

Volume determination of fresh and dried bloodstains by means of optical coherence tomography.

The volume of bloodstains found on crime scenes may help forensic investigators reconstruct the location and kinematics of bloodletting events, as stain size, volume, and impact velocity are related. Optical coherence tomography was used as a method to determine the volume and volume ratio of dried and fresh bloodstains on both glass and irregular surfaces or deposited with an impact velocity. The volume of blood drops deposited on smooth glass surfaces was measured within a deviation of 2%. This deviation increased for droplets on irregular surfaces or deposited with an impact velocity. The volume ratio of dried and fresh bloodstains was equal to 19-28% depending on the individual donor and on the use of an anticoagulant. Optical coherence tomography is a good method to determine the volume of fresh and dried bloodstains in laboratory conditions and allows accurate determination of the dry/fresh ratio.

Diffuse reflectance relations based on diffusion dipole theory for large absorption and reduced scattering.

Diffuse reflectance spectra are used to determine the optical properties of biological samples. In medicine and forensic science, the turbid objects under study often possess large absorption and/or scattering properties. However, data analysis is frequently based on the diffusion approximation to the radiative transfer equation, implying that it is limited to tissues where the reduced scattering coefficient dominates over the absorption coefficient. Nevertheless, up to absorption coefficients of 20 mm-1 at reduced scattering coefficients of 1 and 11.5 mm-1, we observed excellent agreement (r2=0.994) between reflectance measurements of phantoms and the diffuse reflectance equation proposed by Zonios et al. [Appl. Opt.38, 6628-6637 (1999)], derived as an approximation to one of the diffusion dipole equations of Farrell et al. [Med. Phys.19, 879-888 (1992)]. However, two parameters were fitted to all phantom experiments, including strongly absorbing samples, implying that the reflectance equation differs from diffusion theory. Yet, the exact diffusion dipole approximation at high reduced scattering and absorption also showed agreement with the phantom measurements. The mathematical structure of the diffuse reflectance relation used, derived by Zonios et al. [Appl. Opt.38, 6628-6637 (1999)], explains this observation. In conclusion, diffuse reflectance relations derived as an approximation to the diffusion dipole theory of Farrell et al. can analyze reflectance ratios accurately, even for much larger absorption than reduced scattering coefficients. This allows calibration of fiber-probe set-ups so that the object's diffuse reflectance can be related to its absorption even when large. These findings will greatly expand the application of diffuse reflection spectroscopy. In medicine, it may allow the use of blue/green wavelengths and measurements on whole blood, and in forensic science, it may allow inclusion of objects such as blood stains and cloth at crime scenes.

Forensic quest for age determination of bloodstains.

Bloodstains at crime scenes are among the most important types of evidence for forensic investigators. They can be used for DNA-profiling for verifying the suspect's identity or for pattern analysis in order to reconstruct the crime. However, until now, using bloodstains to determine the time elapsed since the crime was committed is still not possible. From a criminalistic point of view, an accurate estimation of when the crime was committed enables to verify witnesses' statements, limits the number of suspects and assesses alibis. Despite several attempts and exploration of many technologies during a century, no method has been materialized into forensic practice. This review gives an overview of an extensive search in scientific literature of techniques that address the quest for age determination of bloodstains. We found that most techniques are complementary to each other, in short as well as long term age determination. Techniques are compared concerning their sensitivity for short and long term ageing of bloodstains and concerning their possible applicability to be used on a crime scene. In addition, experimental challenges like substrate variation, interdonor variation and environmental influences are addressed. Comparison of these techniques contributes to our knowledge of the physics and biochemistry in an ageing bloodstain. Further improvement and incorporation of environmental factors are necessary to enable age determination of bloodstains to be acceptable in court.

Remote spectroscopic identification of bloodstains.

Blood detection and identification at crime scenes are crucial for harvesting forensic evidence. Unfortunately, most tests for the identification of blood are destructive and time consuming. We present a fast and nondestructive identification test for blood, using noncontact reflectance spectroscopy. We fitted reflectance spectra of 40 bloodstains and 35 nonbloodstains deposited on white cotton with spectroscopic features of the main compounds of blood. Each bloodstain was measured 30 times to account for aging effects. The outcome of the blood measurements was compared with the reflectance of blood-mimicking stains and various body fluids. We found that discrimination between blood and nonblood deposited on white cotton is possible with a specificity of 100% and a sensitivity of 98%. In conclusion, a goodness of fit between the sample's reflectance and the blood component fit may allow identification of blood at crime scenes by remote spectroscopy.

Biphasic oxidation of oxy-hemoglobin in bloodstains.

BACKGROUND: In forensic science, age determination of bloodstains can be crucial in reconstructing crimes. Upon exiting the body, bloodstains transit from bright red to dark brown, which is attributed to oxidation of oxy-hemoglobin (HbO(2)) to met-hemoglobin (met-Hb) and hemichrome (HC). The fractions of HbO(2), met-Hb and HC in a bloodstain can be used for age determination of bloodstains. In this study, we further analyze the conversion of HbO(2) to met-Hb and HC, and determine the effect of temperature and humidity on the conversion rates. METHODOLOGY: The fractions of HbO(2), met-Hb and HC in a bloodstain, as determined by quantitative analysis of optical reflectance spectra (450-800 nm), were measured as function of age, temperature and humidity. Additionally, Optical Coherence Tomography around 1300 nm was used to confirm quantitative spectral analysis approach. CONCLUSIONS: The oxidation rate of HbO(2) in bloodstains is biphasic. At first, the oxidation of HbO(2) is rapid, but slows down after a few hours. These oxidation rates are strongly temperature dependent. However, the oxidation of HbO(2) seems to be independent of humidity, whereas the transition of met-Hb into HC strongly depends on humidity. Knowledge of these decay rates is indispensable for translating laboratory results into forensic practice, and to enable bloodstain age determination on the crime scene.

Non-contact spectroscopic determination of large blood volume fractions in turbid media.

We report on a non-contact method to quantitatively determine blood volume fractions in turbid media by reflectance spectroscopy in the VIS/NIR spectral wavelength range. This method will be used for spectral analysis of tissue with large absorption coefficients and assist in age determination of bruises and bloodstains. First, a phantom set was constructed to determine the effective photon path length as a function of µ(a) and µ(s)' on phantoms with an albedo range: 0.02-0.99. Based on these measurements, an empirical model of the path length was established for phantoms with an albedo > 0.1. Next, this model was validated on whole blood mimicking phantoms, to determine the blood volume fractions ρ = 0.12-0.84 within the phantoms (r = 0.993; error < 10%). Finally, the model was proved applicable on cotton fabric phantoms.

Age estimation of blood stains by hemoglobin derivative determination using reflectance spectroscopy.

Blood stains can be crucial in reconstructing crime events. However, no reliable methods are currently available to establish the age of a blood stain on the crime scene. We show that determining the fractions of three hemoglobin derivatives in a blood stain at various ages enables relating these time varying fractions to the age of the blood stain. Application of light transport theory allows addressing the spectroscopic changes in ageing blood stains to changes in chemical composition, i.e. the transition of oxy-hemoglobin into met-hemoglobin and hemichrome. We have found in 20 blood stains that the chemical composition of the blood stain with age, called hemoglobin reaction kinetics, under controlled circumstances, shows a distinct time-dependent behavior, with a unique combination of the three hemoglobin derivatives at all moments in time. Finally, we employed the hemoglobin reaction kinetics inversely to assess the age of 20 other blood stains studied, again over a time period of 0-60 days. We estimated an age of e.g. 55 days correct within an uncertainty margin of 14 days. In conclusion, we propose that the results obtained under controlled conditions demand further evaluation of their possible value for age determination of blood stains on crime scenes.

Optical phantoms of varying geometry based on thin building blocks with controlled optical properties.

Current innovations in optical imaging, measurement techniques, and data analysis algorithms express the need for reliable testing and comparison methods. We present the design and characterization of silicone elastomer-based optical phantoms. Absorption is included by adding a green dye and scattering by adding TiO(2) or SiO(2) particles. Optical coherence tomography measurements demonstrate a linear dependence of the attenuation coefficient with scatterer concentration in the absence of absorbers. Optical transmission spectroscopy of the nonscattering absorbing phantoms shows a linear concentration dependent absorption coefficient. Both types of samples are stable over a period of 6 months. Confocal microscopy of the samples demonstrates a homogeneous distribution of the scatterers, albeit with some clustering. Based on layers with thicknesses as small as 50 mum, we make multifaceted structures resembling flow channels, (wavy) skin-like structures, and a layered and curved phantom resembling the human retina. Finally, we demonstrate the ability to incorporate gold nanoparticles within the phantoms. In conclusion, our phantoms are easy to make, are based on affordable materials, exhibit well-defined and controllable thickness, refractive index, absorption, and scattering coefficients, are homogeneous, and allow the incorporation of novel types of nanoparticle contrast agents. We believe our phantoms fulfill many of the requirements for an "ideal" tissue phantom, and will be particularly suited for novel optical coherence tomography applications.

Heat conduction from the exceedingly hot fiber tip contributes to the endovenous laser ablation of varicose veins.

Lower-extremity venous insufficiency is a common condition, associated with considerable health care costs. Endovenous laser ablation is increasingly used as therapy, but its mechanism of action is insufficiently understood. Here, direct absorption of the laser light, collapsing steam bubbles and direct fiber-wall contact have all been mentioned as contributing mechanisms. Because fiber tips have reported temperatures of 800-1,300 degrees C during endovenous laser ablation, we sought to assess whether heat conduction from the hot tip could cause irreversible thermal injury to the venous wall. We approximated the hot fiber tip as a sphere with diameter equal to the fiber diameter, having a steady state temperature of 800 degrees C or 1,000 degrees C. We computed venous wall temperatures due to heat conduction from this hot sphere, varying the pullback velocity of the fiber and the diameter of the vein. Venous wall temperatures corresponding to irreversible injury resulted for a 3 mm diameter vein and pullback velocities <3 mm/s but not for 5 mm and > or =1 mm/s. The highest wall temperature corresponded to the position on the wall closest to the fiber tip, hence it moves longitudinally in parallel with the moving fiber tip. We concluded that heat conduction from the hot fiber tip is a contributing mechanism in endovenous laser ablation.