C — https://pubmed.ncbi.nlm.nih.gov

Site Health

Score: 75 / 100

Based on 8 categories, 0 sections

Your load time meets Google's 'Good' threshold — fine-tuning can still help.

Good foundation, but a few gaps could be exploited.

Several issues make your site difficult for assistive technology users.

Solid SEO basics — a few optimizations could boost rankings.

Solid infrastructure — fast server responses across the board.

Mostly compliant — a few items need attention.

Missing metadata means poor previews on social media and search.

Lean and efficient — low environmental impact per visit.

How is this calculated?

The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.

Performance 25%Security 25%Accessibility 15%SEO 10%Infrastructure 10%Compliance 8%Content 5%Sustainability 2%

Weights reflect general web best practices. Individual needs may differ.

How the composite score is calculated

How you compare

HSTS · 2214 peers

You 75

Avg 74

At average

0 50 100

Better than 55% of HSTS sites See full HSTS benchmark →

Google Cloud CDN · 102 peers

You 75

Avg 73

At average

0 50 100

Better than 60% of Google Cloud CDN sites See full Google Cloud CDN benchmark →

Top Priorities (5)

Content-Security-Policy header is missing

Security gaps expose your site and users to attacks, eroding trust.

Security › Security Headers

No Content-Security-Policy header found

Security gaps expose your site and users to attacks, eroding trust.

Security › Content Security Policy

No <main> landmark found

Accessibility issues exclude users with disabilities — up to 15% of your potential audience.

Accessibility › Landmark Structure

42 third-party resources (99% of weight)

Performance issues directly impact user engagement and conversion rates.

Performance › Page Weight Inventory

Cookie 'ncbi_sid' has no SameSite attribute

Security gaps expose your site and users to attacks, eroding trust.

Security › Cookie Security

View fix priority matrix

Fix Priority Matrix

5 findings

Impact

Quick Wins

High impact, low effort — start here.

Strategic

High impact, requires investment.

Easy Improvements

Small gains, minimal effort.

Nothing in this quadrant — good news.

Deprioritize

Low impact, high effort — do last.

Nothing in this quadrant — good news.

← Low effort High effort →

Embed this badge

Markdown

[![BeaverCheck](https://beavercheck.com/badge?url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov)](https://beavercheck.com/results/b2217678-60c6-438f-87c9-b3790115d4b6)

HTML

<a href="https://beavercheck.com/results/b2217678-60c6-438f-87c9-b3790115d4b6"><img src="https://beavercheck.com/badge?url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov" alt="BeaverCheck Score"></a>

Image URL

https://beavercheck.com/badge?url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov

This badge auto-updates with your latest scan result.

What fixing these means

Your site performs reasonably well, but a few targeted fixes could meaningfully improve results. Your page blocks user input for 605ms — visitors may think the site is frozen. Accessibility issues exclude users who rely on assistive technology — an estimated 15% of your potential audience. Addressing the critical issues below would have the most immediate impact on your user trust.

3 security gaps detected — browsers may warn visitors about your site.

1 accessibility issue excludes users who rely on assistive technology.

1 performance issue — Akamai's research found 53% of mobile users abandon pages over 3s.

Conversion Barriers

1 critical 5 warning

6 barrier(s) likely increasing bounce by ~19%.

Speed (1)

Page feels frozen for 605ms

+5% bounce

Clicks on the primary CTA are ignored while JavaScript runs

Fix: Break up long tasks; defer non-critical JavaScript to post-hydration

Trust (1)

No Content-Security-Policy header

+1% bounce

Higher XSS blast radius — one compromised script can exfiltrate the checkout form

Fix: Ship a reporting-only CSP first, then enforce once violations are clean

Content (3)

No Open Graph tags

+2% bounce

Links shared on LinkedIn / Slack / Facebook show bare URLs — referral clicks drop

Fix: Add og:title, og:description, og:image, og:url to the page head

No structured data

+2% bounce

No rich-result eligibility in Google — lower SERP CTR vs competitors with stars and prices

Fix: Add JSON-LD for your page type (Product, Article, FAQPage, LocalBusiness, …)

Thin content

+3% bounce

Under 300 words — visitors bounce looking for substance, search engines rank competitors first

Fix: Add a substantive FAQ, product detail, or case-study section

Navigation (1)

No skip-to-content link

+1% bounce

Keyboard and screen-reader users must tab through the entire header on every page

Fix: Add a visible-on-focus <a href="#main">Skip to content</a> as the first focusable element

Preliminary CRO audit — each barrier links to the tab with detailed analysis.

Return on Investment

$500 investment → $0.20/month returns + USD 157,500 risk avoided

Payback period: > 2 years First-year ROI: -100%

Investment

$500

5h · 5 findings

Monthly returns

$0.20 /mo

~$2.41 / year

Bandwidth savings $0.20

Regulatory risk avoided

USD 157,500

if kept compliant

ADA Title III USD 150,000
CCPA/CPRA USD 7,500

$150 — in quick wins — start here for the fastest payback

Figures combine localized regulatory fine ceilings, search/conversion value priced against local CPC, and bandwidth waste estimates. Results depend on implementation quality and audience composition. Not legal or financial advice.

Full methodology & sources

Estimated Remediation Cost

$500

5.0 developer hours at $100/hr

Based on United States rates ($100/hr)

Quick wins

$150 3 fixes in ~90 minutes

Start here for the best return on investment

Cost by category

Cost by effort level

Adjust assumptions

Custom rate

$ /hr

Rates reflect fully-loaded developer cost including overhead

How developer rates are sourced

What Inaction Is Costing You

$13,125 / month at risk

~$157,502 / year if left unfixed

Compliance Risk

$157,500

ADA Title IIICCPA/CPRA

No privacy policy link detected
CCPA/CPRA: USD 2,500 – USD 7,500
Privacy Policy not detected
CCPA/CPRA: USD 2,500 – USD 7,500
No <main> landmark found
ADA Title III: USD 25,000 – USD 150,000

+3 more

Bandwidth Waste

$0.20 /mo

2512.3 MB/mo × 0.080 USD/GB

Optimize transfer: save ~251 KB per page load
Saves $0.20/mo

Compliance figures represent the statutory maximum fine for the most severe triggered category, capped per regulation — not the sum of per-finding penalties. Based on published regulatory fine ranges. This is not legal advice.

Compliance methodology · SEO assumptions · Bandwidth model

Your performance is already good — improvements may show diminishing returns

Monthly visitors

Unique monthly visitors from your analytics

Conversion rate (%)

Purchases, signups, or key actions

Avg. order value

Optional — for revenue estimation

additional conversions/month

more engaged visitors from reduced bounce

potential monthly revenue

Current bounce (est.)

After fixes (est.)

Estimated bounce reduction

Fix 3 critical issues to capture this value

How this is calculated

Based on Google/Deloitte research ("Milliseconds Make Millions") showing a ~7% bounce rate increase per additional second of LCP above the 2.5s "Good" threshold.

Your site's LCP: → estimated after fixes.

These are estimates based on industry research — actual results vary

Bounce-rate model & assumptions

Your data stays in your browser — nothing is sent to our servers

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

Performance

100

Accessibility

100

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.85 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

2.44 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

605 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.007

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

1.91 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

9.63 s

Detailed Report

Audit breakdown by category with detailed findings.

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more ▾

Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Request	Cache TTL	Transfer Size
cdn.ncbi.nlm.nih.gov/core/pinger/pinger.js	3600.0 s	29.4 KiB
/Universal-Federated-Analytics-Min.js?agency=HHS&subagenc...	0.0 ms	9.4 KiB
cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/logos/AgencyLogo.svg	3600.0 s	8.8 KiB
cdn.ncbi.nlm.nih.gov/core/alerts/alerts.js?_=1776797236780	3600.0 s	5.9 KiB
dap.digitalgov.gov/web-vitals/dist/web-vitals.attribution.iife.js	0.0 ms	4.5 KiB
/SIE/?Q_ZID=ZN_dikYWqsjiUWN0Q5	3600.0 s	4.6 KiB
/dxjsmodule/12.1a2b7192fd54e87d3971.chunk.js?Q_CLIENTVERS...	604800.0 s	35.8 KiB
/dxjsmodule/CoreModule.js?Q_CLIENTVERSION=2.46.0&Q_CLIENT...	604800.0 s	30.9 KiB
/dxjsmodule/37.7ea1ffe71ad8c0799cc1.chunk.js?Q_CLIENTVERS...	604800.0 s	18.6 KiB
/dxjsmodule/1.bc67e778235741631577.chunk.js?Q_CLIENTVERSI...	604800.0 s	7.1 KiB
/dxjsmodule/7.f7df015b06d8a90ce822.chunk.js?Q_CLIENTVERSI...	604800.0 s	1.4 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-DIV

nodeLabel: Search: Advanced PubMed® comprises more than 40 million citations for biomedica…

path: 1,HTML,1,BODY,3,DIV,8,MAIN,1,DIV

selector: body > div.site-content > main#home-page > div.intro

snippet: <div class="intro">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.

title: Preconnected origins

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

value: No additional origins are good candidates for preconnecting

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size	Duration
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	5.7 KiB
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	4.2 KiB
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	2.2 KiB
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	19.0 KiB	926 ms

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 150 ms 15.9 KiB

URL	Transfer Size	Est Savings
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	18.4 KiB	15.9 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more ▾

This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.

Source: Google web.dev / Lighthouse

Estimated savings: 150 ms 252.3 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L	147.1 KiB	62.3 KiB
/gtag/js?id=G-DP2X732JSX&l=pingerDataLayer&cx=c&gtm=4e64h1	147.5 KiB	61.5 KiB
www.googletagmanager.com/gtm.js?id=GTM-PC9B6M3&l=pingerDataLayer	129.6 KiB	60.4 KiB
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/js/out...	51.3 KiB	23.7 KiB
/dxjsmodule/12.1a2b7192fd54e87d3971.chunk.js?Q_CLIENTVERS...	35.7 KiB	22.3 KiB
/dxjsmodule/CoreModule.js?Q_CLIENTVERSION=2.46.0&Q_CLIENT...	30.9 KiB	21.9 KiB

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Total CPU Time	Script Evaluation	Script Parse
Unattributable	413 ms	18 ms	0.0 ms
www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L	412 ms	339 ms	58 ms
pubmed.ncbi.nlm.nih.gov/	402 ms	60 ms	3.0 ms
/dxjsmodule/12.1a2b7192fd54e87d3971.chunk.js?Q_CLIENTVERS...	281 ms	251 ms	15 ms
www.googletagmanager.com/gtm.js?id=GTM-PC9B6M3&l=pingerDataLayer	231 ms	182 ms	34 ms
/gtag/js?id=G-DP2X732JSX&l=pingerDataLayer&cx=c&gtm=4e64h1	227 ms	188 ms	31 ms
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/js/out...	90 ms	51 ms	25 ms
cdn.ncbi.nlm.nih.gov/core/pinger/pinger.js	89 ms	68 ms	8.8 ms

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

Category	Time Spent
Script Evaluation	1.3 s
Other	438 ms
Style & Layout	236 ms
Script Parsing & Compilation	218 ms
Rendering	70 ms
Garbage Collection	66 ms
Parse HTML & CSS	26 ms

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL
pubmed logo `form#search-form > div.inner-wrap > a.pubmed-logo > img`	/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/core/images/...
NIH NLM Logo `div.usa-width-one-whole > div.ncbi-header__logo > a.logo > img`	cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/logos/AgencyLogo.svg
U.S. flag `div.usa-accordion > header.usa-banner-header > div.usa-grid > img`	cdn.ncbi.nlm.nih.gov/coreutils/uswds/img/favicons/favicon-57.png

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Layout shift culprits

●Document request latency

●Optimize DOM size

●Font display

●Forced reflow

●Improve image delivery

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●Avoids enormous network payloads Total size was 818 KiB

●User Timing marks and measures 14 user timings

●Avoid long main-thread tasks 9 long tasks found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 20 ms

●Server Backend Latencies 120 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Avoid multiple page redirects

●Initial server response time was short Root document took 160 ms

●Avoid large layout shifts 1 layout shift found

○INP breakdown

○Avoid non-composited animations

100

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

●`[aria-hidden="true"]` is not present on the document `<body>`

●`[role]`s have all required `[aria-*]` attributes

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●Form elements have associated labels

●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

●`[accesskey]` values are unique

●ARIA attributes are used as specified for the element's role

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

●`<html>` element has a `[lang]` attribute

●`<html>` element has a valid value for its `[lang]` attribute

●Links have a discernible name

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●Identical links have the same purpose.

○`button`, `link`, and `menuitem` elements have accessible names

○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.

○`[role]`s are contained by their required parent element

○Elements with the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

○The page contains a heading, skip link, or landmark region

○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.

○Definition list items are wrapped in `<dl>` elements

○ARIA IDs are unique

○No form fields have multiple labels

○`<frame>` or `<iframe>` elements have a title

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○Input buttons have discernible text.

○`<input type="image">` elements have `[alt]` text

○Links are distinguishable without relying on color.

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.

○`[lang]` attributes have a valid value

○`<video>` elements contain a `<track>` element with `[kind="captions"]`

○Tables have different content in the summary attribute and `<caption>`.

○All heading elements contain content.

○Uses ARIA roles only on compatible elements

○Image elements do not have `[alt]` attributes that are redundant text.

○Elements with visible text labels have matching accessible names.

○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`<td>` elements in a large `<table>` have one or more table headers.

100

Best Practices

●Uses HTTPS

●Avoids deprecated APIs

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No browser errors logged to the console

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Use a strong HSTS policy

○Ensure proper origin isolation with COOP

○Mitigate clickjacking with XFO or CSP

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Crawling and Indexing

Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn how to make links crawlable

Why this matters

Performance issues directly impact user engagement and conversion rates.

Uncrawlable Link
See more trending articles `div.homepage-trending-and-latest > div.trending-section > div.trending-articles-see-more > a`

To appear in search results, crawlers need access to your app.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

○robots.txt is valid

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

Performance

100

Accessibility

100

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience. — Desktop

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

628 ms

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

778 ms

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

2 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.000

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

718 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.58 s

Detailed Report

Audit breakdown by category with detailed findings.

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more ▾

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-DIV

nodeLabel: Search: Search Advanced PubMed® comprises more than 40 million citations for bi…

path: 1,HTML,1,BODY,3,DIV,8,MAIN,1,DIV

selector: body > div.site-content > main#home-page > div.intro

snippet: <div class="intro">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

title: Preconnected origins

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

value: No additional origins are good candidates for preconnecting

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size	Duration
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	4.2 KiB
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	5.7 KiB
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	18.6 KiB	265 ms
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	2.6 KiB

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Request	Cache TTL	Transfer Size
cdn.ncbi.nlm.nih.gov/core/pinger/pinger.js	3600.0 s	29.4 KiB
/Universal-Federated-Analytics-Min.js?agency=HHS&subagenc...	0.0 ms	9.4 KiB
cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/logos/AgencyLogo.svg	3600.0 s	8.8 KiB
cdn.ncbi.nlm.nih.gov/core/alerts/alerts.js?_=1776797250764	3600.0 s	5.9 KiB
dap.digitalgov.gov/web-vitals/dist/web-vitals.attribution.iife.js	0.0 ms	4.5 KiB
/SIE/?Q_ZID=ZN_dikYWqsjiUWN0Q5	3600.0 s	4.6 KiB
/dxjsmodule/12.1a2b7192fd54e87d3971.chunk.js?Q_CLIENTVERS...	604800.0 s	35.8 KiB
/dxjsmodule/CoreModule.js?Q_CLIENTVERSION=2.46.0&Q_CLIENT...	604800.0 s	30.9 KiB
/dxjsmodule/37.7ea1ffe71ad8c0799cc1.chunk.js?Q_CLIENTVERS...	604800.0 s	18.6 KiB
/dxjsmodule/1.bc67e778235741631577.chunk.js?Q_CLIENTVERSI...	604800.0 s	7.1 KiB
/dxjsmodule/7.f7df015b06d8a90ce822.chunk.js?Q_CLIENTVERSI...	604800.0 s	1.4 KiB

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Diagnostics

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 15.3 KiB

URL	Transfer Size	Est Savings
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/css/ou...	18.4 KiB	15.3 KiB

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more ▾

Source: Google web.dev / Lighthouse

Estimated savings: 0.0 ms 251.4 KiB

URL	Transfer Size	Est Savings
www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L	147.1 KiB	62.3 KiB
/gtag/js?id=G-DP2X732JSX&l=pingerDataLayer&cx=c&gtm=4e64h1	147.5 KiB	62.2 KiB
www.googletagmanager.com/gtm.js?id=GTM-PC9B6M3&l=pingerDataLayer	129.6 KiB	60.4 KiB
/dxjsmodule/12.1a2b7192fd54e87d3971.chunk.js?Q_CLIENTVERS...	35.7 KiB	22.3 KiB
/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/CACHE/js/out...	51.3 KiB	22.1 KiB
/dxjsmodule/CoreModule.js?Q_CLIENTVERSION=2.46.0&Q_CLIENT...	30.9 KiB	22.0 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL
pubmed logo `form#search-form > div.inner-wrap > a.pubmed-logo > img`	/pubmed/ffd2ec78-62e5-42af-9cba-3b683627d12e/core/images/...
NIH NLM Logo `div.usa-width-one-whole > div.ncbi-header__logo > a.logo > img`	cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/logos/AgencyLogo.svg
U.S. flag `div.usa-accordion > header.usa-banner-header > div.usa-grid > img`	cdn.ncbi.nlm.nih.gov/coreutils/uswds/img/favicons/favicon-57.png

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Time to Interactive 1.6 s

●Layout shift culprits

●Document request latency

●Optimize DOM size

●Font display

●Forced reflow

●Improve image delivery

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Max Potential First Input Delay 50 ms

●Minify CSS

●Minify JavaScript

●Avoids enormous network payloads Total size was 816 KiB

●User Timing marks and measures 14 user timings

●JavaScript execution time 0.3 s

●Minimizes main-thread work 0.6 s

●Avoid long main-thread tasks 1 long task found

●Avoid non-composited animations 1 animated element found

●Page didn't prevent back/forward cache restoration

●Network Requests

●Network Round Trip Times 20 ms

●Server Backend Latencies 110 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Avoid multiple page redirects

●Initial server response time was short Root document took 140 ms

○INP breakdown

○Avoid large layout shifts

100

Accessibility

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

●`[aria-hidden="true"]` is not present on the document `<body>`

●`[role]`s have all required `[aria-*]` attributes

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●Form elements have associated labels

●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

●`[accesskey]` values are unique

●ARIA attributes are used as specified for the element's role

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

●`<html>` element has a `[lang]` attribute

●`<html>` element has a valid value for its `[lang]` attribute

●Links have a discernible name

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Skip links are focusable.

●Document has a main landmark.

●Deprecated ARIA roles were not used

●Identical links have the same purpose.

●Elements with visible text labels have matching accessible names.

○`button`, `link`, and `menuitem` elements have accessible names

○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.

○`[role]`s are contained by their required parent element

○Elements with the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

○The page contains a heading, skip link, or landmark region

○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.

○Definition list items are wrapped in `<dl>` elements

○ARIA IDs are unique

○No form fields have multiple labels

○`<frame>` or `<iframe>` elements have a title

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○Input buttons have discernible text.

○`<input type="image">` elements have `[alt]` text

○Links are distinguishable without relying on color.

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.

○`[lang]` attributes have a valid value

○`<video>` elements contain a `<track>` element with `[kind="captions"]`

○Tables have different content in the summary attribute and `<caption>`.

○All heading elements contain content.

○Uses ARIA roles only on compatible elements

○Image elements do not have `[alt]` attributes that are redundant text.

○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`<td>` elements in a large `<table>` have one or more table headers.

100

Best Practices

●Uses HTTPS

●Avoids deprecated APIs

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No browser errors logged to the console

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Mitigate DOM-based XSS with Trusted Types

●Detected JavaScript libraries

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Use a strong HSTS policy

○Ensure proper origin isolation with COOP

○Mitigate clickjacking with XFO or CSP

SEO

Crawling and Indexing

Why this matters

Performance issues directly impact user engagement and conversion rates.

Uncrawlable Link
See more trending articles `div.homepage-trending-and-latest > div.trending-section > div.trending-articles-see-more > a`

To appear in search results, crawlers need access to your app.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links have descriptive text

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

○robots.txt is valid

Results for https://pubmed.ncbi.nlm.nih.gov

Site Health

How you compare

Top Priorities (5)

Fix Priority Matrix

Quick Wins

Strategic

Easy Improvements

Deprioritize

What fixing these means

Conversion Barriers

Speed (1)

Trust (1)

Content (3)

Navigation (1)

Return on Investment

Investment

Monthly returns

Regulatory risk avoided

Estimated Remediation Cost

Cost by category

Cost by effort level

What Inaction Is Costing You

Compliance Risk

Bandwidth Waste

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Best Practices

SEO

Crawling and Indexing

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Best Practices

SEO

Crawling and Indexing

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