About

Jeffrey H. Silber, MD, PhD, is an Emeritus Professor of Pediatrics (Oncology) at the University of Pennsylvania's Perelman School of Medicine. He holds additional roles as a Senior Fellow at the Leonard Davis Institute of Health Economics at the Wharton School and as an Associate Scholar at the Center for Clinical Epidemiology and Biostatistics at the University of Pennsylvania School of Medicine. His educational background includes an A.B. from Washington University in Economics, an M.D. from Johns Hopkins Medical School, and a Ph.D. from the University of Pennsylvania in Health Care Systems, with additional honorary recognition as a Masters Degree in Philosophy from the University of Pennsylvania. His contact information is associated with The Children’s Hospital of Philadelphia and the Center for Outcomes Research. The page indicates his involvement in research, clinical, and academic activities within the fields of pediatrics and oncology.

Research topics

• Intensive care medicine
• Medicine
• Internal medicine
• Emergency medicine
• Nursing

Selected publications

• Improving the Evaluation of Low-Volume Hospitals

  Medical Care · 2026-02-02

  article1st authorCorresponding

  BACKGROUND AND OBJECTIVE: Low volume has been recognized as a problem when benchmarking hospitals due to outcome rate instability. We asked if low-volume hospital outcomes, using matching to control for many clinical and sociodemographic characteristics, would expose quality problems not observed with CMS methods. RESEARCH DESIGN: Matched cohort study. Grades derive from mortality differences between all patients at the low-volume hospital and their matched controls. SUBJECTS: Medicare patients admitted with Acute Myocardial Infarction, Heart Failure and Pneumonia in 78 low-volume Pennsylvania acute care hospitals (combined condition volume=75≤N≤750 for the 3 y, 2017-2019), using Medicare's Virtual Research Data Center. MEASURES: Thirty-day mortality. RESULTS: Using matching, 10 of 78 reportable low-volume hospitals had significantly higher mortality versus matched typical controls and 16 low-volume hospitals displayed significantly higher mortality versus well-resourced controls. In contrast, Medicare reported that only 3 of these same 78 hospitals had significantly higher mortality than "the national rate" on AMI, HF, or pneumonia. CONCLUSIONS: We find that some low-volume hospitals performed well. Other low-volume hospitals had significantly worse outcomes than both well-resourced and typical hospitals; and some displayed significantly worse mortality compared with well-resourced controls but did not reach significant differences from typical controls. In short, performing "no different from the national rate," as is almost always reported for low-volume hospitals when using CMS methods, does not imply a low-volume hospital has acceptable outcomes. Reports based on matching can expose low-volume hospital quality problems not apparent using standard methods. Low-volume hospitals have more quality problems than generally reported.

  PublisherDOI

• Validation of the DESI-DR1 3x2-pt analysis: scale cut and shear ratio tests

  The Open Journal of Astrophysics · 2026-03-31

  preprintOpen access

  Combined survey analyses of galaxy clustering and weak gravitational lensing (3x2-pt studies) will allow new and accurate tests of the standard cosmological model. However, careful validation is necessary to ensure that these cosmological constraints are not biased by uncertainties associated with the modelling of astrophysical or systematic effects. In this study we validate the combined 3x2-pt analysis of the Dark Energy Spectroscopic Instrument Data Release 1 (DESI-DR1) spectroscopic galaxy clustering and overlapping weak lensing datasets from the Kilo-Degree Survey (KiDS), the Dark Energy Survey (DES), and the Hyper-Suprime-Cam Survey (HSC). By propagating the modelling uncertainties associated with the non-linear matter power spectrum, non-linear galaxy bias and baryon feedback, we design scale cuts to ensure that measurements of the matter density and the amplitude of the matter power spectrum are biased by less than 30% of the statistical error. We also test the internal consistency of the data and weak lensing systematics by performing new measurements of the lensing shear ratio. We demonstrate that the DESI-DR1 shear ratios can be successfully fit by the same model used to describe cosmic shear correlations, and analyse the additional information that can be extracted about the source redshift distributions and intrinsic alignment parameters. This study serves as crucial preparation for the upcoming cosmological parameter analysis of these datasets.

  PublisherDOI

• DESI Data Release 1: Stellar Catalogue

  The Open Journal of Astrophysics · 2026-01-12 · 6 citations

  articleOpen access

  In this paper we present the stellar Value-Added Catalogue (VAC) based on the DESI Data Release 1. This VAC contains stellar parameter, abundance and radial velocity measurements for more than 4 million stars. It also contains, for the first time, measurements from individual epochs for more than a million stars with at least two observations. The main contribution to the catalogue comes from the bright program of the main survey, which includes <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>∼</mml:mo> </mml:math> 2.5 million stars, and the backup program, which includes <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>∼</mml:mo> </mml:math> 1 million stars. The combined magnitude range for the stars in the catalogue extends from Gaia G <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mo>∼</mml:mo> <mml:mn>12</mml:mn> </mml:mrow> </mml:math> to G <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mo>∼</mml:mo> <mml:mn>21</mml:mn> </mml:mrow> </mml:math> . For the magnitude range <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>17.5</mml:mn> <mml:mo>&lt;</mml:mo> <mml:mi>G</mml:mi> <mml:mo>&lt;</mml:mo> <mml:mn>21</mml:mn> </mml:mrow> </mml:math> this catalogue represents a factor of 10 increase in the number of stars with radial velocity and abundance measurements compared to existing surveys. Despite DESI’s resolution (R <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mo>∼</mml:mo> <mml:mn>2500</mml:mn> <mml:mo>−</mml:mo> <mml:mn>5000</mml:mn> </mml:mrow> </mml:math> ), the median radial velocity uncertainty for stars in the catalogue is better than 1 km s. The stellar parameters and abundances of stars in DESI are measured by two independent pipelines, and after applying a temperature-dependent calibration, [Fe/H] abundances of high signal-to-noise stars are accurate to better than <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>∼</mml:mo> </mml:math> 0.1 dex when compared to high-resolution surveys. The catalogue probes different Galactic components including a particularly large number of distant stars: tens of thousands of stars further than 10 kpc, and thousands further than 50 kpc. The catalogue also contains several thousand extremely metal-poor stars with . The released sample of stars includes measurements for thousands of stars that are members of dwarf galaxies, open and globular clusters as well as members of several dozen stellar streams. The next public DESI data release is expected in less than two years and will contain three times as many stars as DR1.

  PublisherDOI

• DESI DR2 Galaxy Luminosity Functions

  Monthly Notices of the Royal Astronomical Society · 2026-05-07

  articleOpen access

  Abstract We present galaxy luminosity functions (LFs) for the Dark Energy Spectroscopic Instrument (DESI) DR2 Bright Galaxy Survey (BGS) in the g, r, z, and w1 bands over 0.002 &amp;lt; z &amp;lt; 0.6. Our analysis uses updated k-corrections and evolutionary corrections, including new polynomial k-correction fits derived from BGS Year 1 data that supersede earlier GAMA-based prescriptions. Exploiting the statistical power of DESI, we measure LFs to very faint magnitudes, reaching 0.1Mr − 5log h ~ −10. Independent measurements from the North and South survey regions show excellent agreement around the LF knee, but the very small statistical uncertainties reveal that simple analytic forms fail to capture the full LF shape. The bright end departs from a pure exponential decline, while the faint end exhibits complex, non-power-law behaviour, including a pronounced upturn at 0.1Mr − 5log h ≳ −15, which is stronger for red galaxies than for blue. We show that our LFs are largely complete for galaxies with surface brightness μ50 &amp;lt; 25, and that an apparent steepening fainter than −13 is driven primarily by local overdensity and fragmentation of large galaxies. A systematic North-South offset at the brightest magnitudes is traced to red galaxies and may reflect shallower North photometry underestimating extended early-type profiles, although this remains inconclusive. We therefore also provide LFs based on model-Petrosian magnitudes. Redshift-splitting reveals small but significant residuals, indicating limitations of a simple global evolutionary model. Using the redshift limits of Loveday et al. (2012), we find excellent agreement with GAMA, with substantially reduced statistical errors. These measurements provide a precise reference for studies of environmental and population-dependent LFs and for testing galaxy formation models.

  PublisherDOI

• DESI-DR1 <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mn>3</a:mn> <a:mo>×</a:mo> <a:mn>2</a:mn> </a:math> -pt analysis: consistent cosmology across weak lensing surveys

  The Open Journal of Astrophysics · 2026-04-28

  preprintOpen access

  We present a joint cosmological analysis of projected galaxy clustering observations from the Dark Energy Spectroscopic Instrument Data Release 1 (DESI-DR1), and overlapping weak gravitational lensing observations from three datasets: the Kilo-Degree Survey (KiDS-1000), the Dark Energy Survey (DES-Y3), and the Hyper-Suprime-Cam Survey (HSC-Y3). This combination of large-scale structure probes allows us to measure a set of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>3</mml:mn> <mml:mo>×</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:math> -pt correlation functions, breaking the degeneracies between parameters in cosmological fits to individual observables. We obtain mutually-consistent constraints on the parameter from the combination of DESI-DR1 and DES-Y3, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msub> <mml:mi>S</mml:mi> <mml:mn>8</mml:mn> </mml:msub> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mn>0.760</mml:mn> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.018</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.020</mml:mn> </mml:mrow> </mml:msubsup> </mml:mrow> </mml:math> from KiDS-1000, and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msub> <mml:mi>S</mml:mi> <mml:mn>8</mml:mn> </mml:msub> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mn>0.771</mml:mn> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.027</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.026</mml:mn> </mml:mrow> </mml:msubsup> </mml:mrow> </mml:math> from HSC-Y3. These parameter determinations are consistent with fits to the Planck Cosmic Microwave Background dataset, albeit with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>1.5</mml:mn> <mml:mo>−</mml:mo> <mml:mn>2</mml:mn> <mml:mi>σ</mml:mi> </mml:mrow> </mml:math> lower values in the plane. We perform our analysis with a unified pipeline tailored to the requirements of each cosmic shear survey, which self-consistently determines cosmological and astrophysical parameters. We generate an analytical covariance matrix for the correlation data including all cross-covariances between probes, and we design a new blinding procedure to safeguard our analysis against confirmation bias, whilst leaving goodness-of-fit statistics unchanged. Our study is part of a suite of papers that present joint cosmological analyses of DESI-DR1 and weak gravitational lensing datasets.

  PublisherDOI

• The Backup Program of the Dark Energy Spectroscopic Instrument’s Milky Way Survey

  The Astronomical Journal · 2026-05-13

  articleOpen access

  Abstract The Milky Way Backup Program (MWBP), a survey currently underway with the Dark Energy Spectroscopic Instrument (DESI) on the Nicholas U. Mayall 4 m Telescope, works at the margins of the DESI Main surveys to obtain spectra of millions of additional stars from the Gaia catalog. Efficiently utilizing times between ∼12° and 18° twilight and poor weather conditions, the MWBP extends the range of stellar sources studied to both brighter magnitudes and lower Galactic latitude and declination than the stars studied in DESI’s Main Milky Way Survey. While the MWBP prioritizes candidate giant stars selected from the Gaia catalog (using color and parallax criteria), it also includes an unbiased sample of bright stars (i.e., 11.2 ≲ G &lt; 16 mag) as well as fainter sources (to G ≲ 19 mag). As of 2025 March 1, the survey had obtained spectra of ∼7 million stars, approximately 1.2 million of which are included in the DESI Data Release 1. The DESI spectra cover the wavelength range from 3600 to 9800 Å at a resolution λ /Δ λ varying from 2000 to 5000. The full survey, when completed, will cover an area of more than 21,000 deg 2 and include approximately 10 million Gaia sources, roughly equal to the number of stellar spectra obtained through the DESI Main Survey, while only utilizing ≈9% of all DESI observing time. This paper provides an overview of the MWBP, describing the target selection, observing strategy, and an introduction to the resulting data.

  PublisherDOI

• Joint cosmological fits to DESI-DR1 full-shape clustering and weak gravitational lensing in configuration space

  The Open Journal of Astrophysics · 2026-05-18

  preprintOpen access

  We present a joint <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>3</mml:mn> <mml:mo>×</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:math> -pt cosmological analysis of auto- and cross-correlations between the Dark Energy Spectroscopic Instrument Data Release 1 (DESI-DR1) Bright Galaxy Survey (BGS) and Luminous Red Galaxy (LRG) samples and overlapping shear measurements from the KiDS-1000, DES-Y3 and HSC-Y3 weak lensing surveys. We perform our analysis in configuration space and, in addition to the cosmic shear correlation functions for each weak lensing dataset, we fit the tangential shear of the weak lensing source galaxies around DESI lens galaxies. Finally, we make use of the anisotropic BGS and LRG clustering information by fitting the full shape of the two-point correlation function multipoles measured over the full DESI-DR1 footprint, presenting the first full-shape analysis of DESI measurements in configuration space. We find that the addition of weak lensing information serves to improve, with respect to the clustering-only case, the measurements of the power spectrum amplitude parameters and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msub> <mml:mi>σ</mml:mi> <mml:mn>12</mml:mn> </mml:msub> </mml:math> by <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>15</mml:mn> <mml:mi>%</mml:mi> </mml:mrow> </mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>36</mml:mn> <mml:mi>%</mml:mi> </mml:mrow> </mml:math> , respectively. It also improves measurements of the linear bias of the lens galaxies by <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>15</mml:mn> <mml:mo>−</mml:mo> <mml:mn>20</mml:mn> <mml:mi>%</mml:mi> </mml:mrow> </mml:math> , depending on the tracer. Our results show excellent consistency, regardless of the weak lensing survey considered, and are furthermore consistent with a companion analysis that fits <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>3</mml:mn> <mml:mo>×</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:math> -pt correlations including DESI projected clustering measurements, as well as the results published by the weak lensing collaborations themselves. Our measured values for weak lensing amplitude are <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msubsup> <mml:mi>S</mml:mi> <mml:mn>8</mml:mn> <mml:mrow> <mml:mi mathvariant="normal">D</mml:mi> <mml:mi mathvariant="normal">E</mml:mi> <mml:mi mathvariant="normal">S</mml:mi> <mml:mi mathvariant="normal">I</mml:mi> <mml:mo mathvariant="normal">×</mml:mo> <mml:mi mathvariant="normal">H</mml:mi> <mml:mi mathvariant="normal">S</mml:mi> <mml:mi mathvariant="normal">C</mml:mi> </mml:mrow> </mml:msubsup> <mml:mo>=</mml:mo> <mml:mn>0.787</mml:mn> <mml:mo>±</mml:mo> <mml:mn>0.020</mml:mn> </mml:mrow> </mml:math> , <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msubsup> <mml:mi>S</mml:mi> <mml:mn>8</mml:mn> <mml:mrow> <mml:mi mathvariant="normal">D</mml:mi> <mml:mi mathvariant="normal">E</mml:mi> <mml:mi mathvariant="normal">S</mml:mi> <mml:mi mathvariant="normal">I</mml:mi> <mml:mo mathvariant="normal">×</mml:mo> <mml:mi mathvariant="normal">D</mml:mi> <mml:mi mathvariant="normal">E</mml:mi> <mml:mi mathvariant="normal">S</mml:mi> </mml:mrow> </mml:msubsup> <mml:mo>=</mml:mo> <mml:mn>0.791</mml:mn> <mml:mo>±</mml:mo> <mml:mn>0.016</mml:mn> </mml:mrow> </mml:math> , <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msubsup> <mml:mi>S</mml:mi> <mml:mn>8</mml:mn> <mml:mrow> <mml:mi mathvariant="normal">D</mml:mi> <mml:mi mathvariant="normal">E</mml:mi> <mml:mi mathvariant="normal">S</mml:mi> <mml:mi mathvariant="normal">I</mml:mi> <mml:mo mathvariant="normal">×</mml:mo> <mml:mi mathvariant="normal">K</mml:mi> <mml:mi mathvariant="normal">i</mml:mi> <mml:mi mathvariant="normal">D</mml:mi> <mml:mi mathvariant="normal">S</mml:mi> </mml:mrow> </mml:msubsup> <mml:mo>=</mml:mo> <mml:mn>0.771</mml:mn> <mml:mo>±</mml:mo> <mml:mn>0.017</mml:mn> </mml:mrow> </mml:math> , which are <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mn>1.9</mml:mn> <mml:mi>σ</mml:mi> <mml:mo>−</mml:mo> <mml:mn>2.9</mml:mn> <mml:mi>σ</mml:mi> </mml:mrow> </mml:math> below the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msub> <mml:mi>S</mml:mi> <mml:mn>8</mml:mn> </mml:msub> </mml:math> value preferred by Planck. Finally, our clustering-only results are in good agreement with the Fourier space full-shape analysis of all DESI tracers, although we see some indications of the presence of projection effects. This work paves the way for future ‘same-sky’ analyses of cross-correlations between the upcoming DESI data releases and overlapping shear datasets.

  PublisherDOI

• Reporting Failure to Rescue Lands in Europe

  JAMA Network Open · 2026-02-04

  articleOpen access1st authorCorresponding
  PublisherOA PDFDOI

• Model-independent measurement of the matter-radiation equality scale in DESI 2024

  Physical review. D/Physical review. D. · 2025-09-24 · 6 citations

  articleOpen access

  DESI Collaboration: B. Bahr-Kalus et al.

  PublisherOA PDFDOI

• Intrinsic alignment demographics for next-generation lensing: Revealing galaxy property trends with DESI Y1 direct measurements

  ArXiv.org · 2025-07-15 · 2 citations

  preprintOpen access

  We present direct measurements of the intrinsic alignments (IA) of over 2 million spectroscopic galaxies using DESI Data Release 1 and imaging from four lensing surveys: DES, HSC, KiDS, and SDSS. In this uniquely data-rich regime, we take initial steps towards a more tailored IA modelling approach by building a library of IA measurements across colour, luminosity, stellar mass, and redshift. We map the dependence between galaxy type -- in terms of rest-frame colour, strength of the 4000 Angstrom break, and specific star formation rate -- and IA amplitude; the bluest galaxies have an alignment consistent with zero, across low ($0.05

  PublisherOA PDFDOI

Recent grants

• NIH Grant R01HL050424

  NIH · $3.5M · 2003

• NIH Grant R01DK073671

  NIH · $3.1M · 2012

• Understanding Racial Disparities in Surgical Outcomes

  NIH · $1.9M · 2009–2015

• NIH Grant R01HS006560

  NIH · $653k · 1995

• Improving the Framework for Healthcare Public Reporting

  NIH · $871k · 2012–2016

Frequent coauthors

• Orit Even‐Shoshan

  Children's Hospital of Philadelphia

  225 shared

• Paul R. Rosenbaum

  University of Pennsylvania

  209 shared

• Kevin G. Volpp

  University of Pennsylvania

  98 shared

• Richard N. Ross

  Children's Hospital of Philadelphia

  85 shared

• Rachel R. Kelz

  University of Pennsylvania

  74 shared

• Lee A. Fleisher

  66 shared

• Bijan A. Niknam

  Harvard University

  58 shared

• Joseph G. Reiter

  Children's Hospital of Philadelphia

  58 shared

Education

• B.A., Department of Economics

  Washington University

  1976

• M.D.

  Johns Hopkins Medical School

  1980

• Ph.D., Department of Health Care Systems, The Graduate Group in Managerial Science and Applied Economics

  The University of Pennsylvania

  1990

• M.A., Philosophy

  The University of Pennsylvania

  1997

Awards & honors

• Honorary Masters Degree, Philosophy, The University of Penns…