What is the Gera US Hospital Quality Index?

The Gera US Hospital Quality Index (GHQI) is a single 0-100 figure summarising hospital quality for a hospital or a state. It rescales the CMS Overall Star Rating (1-5) onto 0-100 and adds a small, capped adjustment based on CMS mortality and readmission outcomes. Across all 3,182 rated US hospitals it is 55.1.

Is the Gera US Hospital Quality Index a CMS rating?

No. CMS publishes the underlying star rating and measure results; the GHQI is Gera’s transparent summary of those CMS figures into one comparable number. CMS remains the sole rating authority, and Gera reports each hospital’s CMS star rating exactly as published.

Is the score reproducible?

Yes. Every input is the real, published CMS April 2026 'Hospital General Information' open data, a U.S. federal government work in the public domain. The formula above is the complete calculation — anyone can download the same file and reproduce every score exactly. Gera invents no numbers.

Why exclude unrated hospitals?

Many Medicare-registered hospitals (for example most psychiatric, children’s and some critical-access hospitals) do not receive an Overall Star Rating because they do not report enough of the underlying measures. Counting them as zero would misrepresent the data, so they are excluded from both the distribution and the index. Only hospitals with a real published star rating are counted.

Which state scores highest?

On the April 2026 data, Utah scores highest on the Gera US Hospital Quality Index (81.4/100, mean 4.24 stars), and Mississippi lowest (32.8/100). All figures derive from CMS’s own star ratings and measure results.

Gera US Hospital Quality Index — Methodology

The complete, reproducible formula behind the Gera US Hospital Quality Index, computed only from real CMS April 2026 data.

The formula

base = (stars − 1) ÷ 4 × 100

adj = clamp( 3·mortNet + 3·readmNet , −6 , +6 )

GHQI = round( clamp(base + adj, 0, 100) , 1 )

where mortNet and readmNet = (better − worse) ÷ (better + no-different + worse) for the CMS mortality and readmission measure groups. A 5-star hospital scores 100, a 3-star ≈ 50, a 1-star 0, fine-tuned ±6 by outcomes. A state's GHQI is the mean across its rated hospitals.

Step by step

Take the real CMS star rating. For each hospital, read its official CMS Overall Star Rating (1-5) from the CMS Hospital Care Compare 'Hospital General Information' open data (April 2026). Hospitals whose rating is 'Not Available' are excluded entirely — never inferred or estimated.
Rescale the star rating onto 0-100. base = (stars − 1) ÷ 4 × 100. A 1-star hospital scores 0, a 5-star hospital scores 100, and a 3-star hospital scores 50.
Add a capped CMS outcome adjustment. For the mortality and readmission measure groups, CMS reports how many of a hospital’s measures are statistically better or worse than the national rate. For each group, net = (better − worse) ÷ (better + no-different + worse). The adjustment is 3·mortNet + 3·readmNet, clamped to the range −6 to +6 points.
Combine, clamp and average. GHQI(hospital) = clamp(base + adjustment, 0, 100), rounded to one decimal. A state’s GHQI is the simple mean of the GHQI of its rated hospitals. The CMS star rating dominates; the outcome adjustment only fine-tunes hospitals with the same star rating.

Gera US Hospital Quality Index by state (April 2026)

Gera US Hospital Quality Index by state, best first
Rank	State	Rated hospitals	4-5 star	GHQI
1	Utah	29	79.3%	81.4 / 100
2	Colorado	49	73.5%	74.1 / 100
3	South Dakota	18	72.2%	72.2 / 100
4	Wisconsin	86	64.0%	69.5 / 100
5	Minnesota	57	63.2%	69.3 / 100
6	Virginia	76	60.5%	67 / 100
7	Ohio	128	53.1%	64.4 / 100
8	Idaho	22	45.5%	63.8 / 100
9	Rhode Island	11	63.6%	63.5 / 100
10	Nebraska	36	63.9%	62.5 / 100
11	Pennsylvania	132	56.1%	62.1 / 100
12	South Carolina	49	49.0%	60.5 / 100
13	Connecticut	26	46.2%	60.4 / 100
14	Wyoming	16	43.8%	59.5 / 100
15	Texas	217	47.9%	59.4 / 100
16	Indiana	91	44.0%	59 / 100
17	Maryland	42	38.1%	57.6 / 100
18	North Carolina	90	44.4%	57.4 / 100
19	Oklahoma	62	45.2%	57.3 / 100
20	North Dakota	16	43.8%	56.6 / 100
21	Vermont	12	33.3%	56.4 / 100
22	Montana	20	40.0%	56.3 / 100
23	Oregon	44	45.5%	56.3 / 100
24	Iowa	62	45.2%	55.9 / 100
25	Washington	60	40.0%	55.8 / 100
26	Maine	24	41.7%	55.2 / 100
27	Massachusetts	54	38.9%	54.9 / 100
28	Kansas	55	41.8%	54.6 / 100
29	Hawaii	11	45.5%	54.3 / 100
30	New Hampshire	23	43.5%	54.3 / 100
31	Missouri	80	41.2%	53.3 / 100
32	New Jersey	61	39.3%	53.2 / 100
33	Arizona	55	32.7%	52.5 / 100
34	California	280	41.4%	52.4 / 100
35	Michigan	94	38.3%	52.2 / 100
36	Tennessee	72	36.1%	51.9 / 100
37	Florida	169	36.7%	51.4 / 100
38	Illinois	136	36.0%	50.6 / 100
39	Nevada	25	28.0%	49.7 / 100
40	Georgia	84	32.1%	48.4 / 100
41	Alaska	10	30.0%	47.2 / 100
42	Arkansas	44	25.0%	45.7 / 100
43	Louisiana	59	22.0%	45.1 / 100
44	New York	136	26.5%	44.1 / 100
45	Kentucky	67	23.9%	43.8 / 100
46	West Virginia	34	26.5%	43.7 / 100
47	Alabama	59	18.6%	42.5 / 100
48	New Mexico	23	17.4%	37 / 100
49	Mississippi	52	13.5%	32.8 / 100

For context, the US-wide Gera US Hospital Quality Index across all 3,182 rated hospitals is 55.1/100, with 41.9% rated 4 or 5 stars (mean 3.21 stars).

Why this index, and what it is not

A 1-5 star rating plus five separate measure groups is hard to compare across states at a glance. The Gera US Hospital Quality Index collapses the CMS rating and outcomes into one transparent, reproducible 0-100 number so two states can be compared directly. It summarises CMS's own data — it is not a Gera rating of any individual hospital, and it does not replace reading the latest detail on CMS Hospital Care Compare before you choose care.

Gera US Hospital Quality Index: frequently asked questions

What is the Gera US Hospital Quality Index?: The Gera US Hospital Quality Index (GHQI) is a single 0-100 figure summarising hospital quality for a hospital or a state. It rescales the CMS Overall Star Rating (1-5) onto 0-100 and adds a small, capped adjustment based on CMS mortality and readmission outcomes. Across all 3,182 rated US hospitals it is 55.1.
Is the Gera US Hospital Quality Index a CMS rating?: No. CMS publishes the underlying star rating and measure results; the GHQI is Gera’s transparent summary of those CMS figures into one comparable number. CMS remains the sole rating authority, and Gera reports each hospital’s CMS star rating exactly as published.
Is the score reproducible?: Yes. Every input is the real, published CMS April 2026 'Hospital General Information' open data, a U.S. federal government work in the public domain. The formula above is the complete calculation — anyone can download the same file and reproduce every score exactly. Gera invents no numbers.
Why exclude unrated hospitals?: Many Medicare-registered hospitals (for example most psychiatric, children’s and some critical-access hospitals) do not receive an Overall Star Rating because they do not report enough of the underlying measures. Counting them as zero would misrepresent the data, so they are excluded from both the distribution and the index. Only hospitals with a real published star rating are counted.
Which state scores highest?: On the April 2026 data, Utah scores highest on the Gera US Hospital Quality Index (81.4/100, mean 4.24 stars), and Mississippi lowest (32.8/100). All figures derive from CMS’s own star ratings and measure results.

Explore the data

Contains public sector information published by Centers for Medicare & Medicaid Services and licensed under the U.S. Public Domain (federal government work). Source: Centers for Medicare & Medicaid Services — Hospital Care Compare (Hospital General Information) (April 2026, published 28 April 2026).