Skip to content
https://iarc.fr

Lighthouse Desktop

· 0 checks — Desktop Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.
SCORE
0
GRADE
FIX
0
REVIEW
0
PASS
0
INFO
0

Detailed Report

Audit breakdown by category with detailed findings.

77

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

Performance issues directly impact user engagement and conversion rates.

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.

RequestCache TTLTransfer Size
www.iarc.who.int/wp-content/uploads/2026/03/homepage_banner_141.jpg3600.0 s159.5 KiB
/wp-content/uploads/2026/03/Banner_homepage-World-Health-...3600.0 s138.2 KiB
www.iarc.who.int/wp-content/uploads/2026/02/cytoST_IARC-homepage.jpg3600.0 s118.8 KiB
www.iarc.who.int/wp-content/uploads/2026/01/Homepage_banner-IICC2026.jpg3600.0 s103.9 KiB
www.iarc.who.int/wp-content/uploads/2023/02/homepage-research-websites.jpg3600.0 s97.6 KiB
www.iarc.who.int/wp-content/uploads/2025/07/pr368_vignette.jpg3600.0 s85.9 KiB
www.iarc.who.int/wp-content/uploads/2026/03/vignette-pr378-ECAC5.jpg3600.0 s85.5 KiB
www.iarc.who.int/wp-content/uploads/2023/02/mono-handbooks-poster.jpg3600.0 s83.8 KiB
www.iarc.who.int/wp-content/uploads/2026/01/WCD2026-vignette02.jpg3600.0 s80.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/fonts/Object-Sans-700.woff0.0 ms61.5 KiB
/wp-content/uploads/2026/03/vignette_featured-news-world-...3600.0 s76.6 KiB
www.iarc.who.int/wp-content/uploads/2026/04/world-healthday-iarc-oms.jpg3600.0 s73.8 KiB
www.iarc.who.int/wp-content/uploads/2023/02/governance.jpg3600.0 s72.7 KiB
www.iarc.who.int/wp-content/uploads/2024/07/recent-covers-monographs.jpg3600.0 s71.7 KiB
www.iarc.who.int/wp-content/uploads/2023/02/GCO-vignette-homepage.jpg3600.0 s67.8 KiB
www.iarc.who.int/wp-content/uploads/2023/02/dir-gc62-vignette2020-web.jpg3600.0 s65.8 KiB
www.iarc.who.int/wp-content/uploads/2023/02/nc-vignette.jpg3600.0 s65.1 KiB
www.iarc.who.int/wp-content/uploads/2023/10/iarc-video.jpg3600.0 s64.0 KiB
/wp-content/uploads/2026/04/Vignette-for-IARC-publication...3600.0 s63.9 KiB
www.iarc.who.int/wp-content/uploads/2023/02/mts-web-photo-card.jpg3600.0 s63.4 KiB
www.iarc.who.int/wp-content/uploads/2026/02/cytoST_Publications-carousel.jpg3600.0 s62.3 KiB
www.iarc.who.int/wp-content/uploads/2026/04/biobankIARC-2026-vignette.jpg3600.0 s61.9 KiB
www.iarc.who.int/wp-content/uploads/2023/02/etr-elearning-web.jpg3600.0 s61.3 KiB
www.iarc.who.int/wp-content/uploads/2026/02/Publications-carousel_137.jpg3600.0 s60.5 KiB
www.iarc.who.int/wp-content/uploads/2025/09/ESB6-Vignette_op1.jpg3600.0 s58.9 KiB
www.iarc.who.int/wp-content/uploads/2023/02/videos-photo-card.jpg3600.0 s58.8 KiB
www.iarc.who.int/wp-content/uploads/2023/02/summer-school-lcb-website.jpg3600.0 s58.4 KiB
/wp-content/uploads/2025/12/Publications-carousel-BB-eyes...3600.0 s58.1 KiB
www.iarc.who.int/wp-content/uploads/2026/03/vignette-featurednews-mono141.jpg3600.0 s54.6 KiB
www.iarc.who.int/wp-content/uploads/2023/02/newsletter-photo-card-web.jpg3600.0 s54.1 KiB
www.iarc.who.int/wp-content/uploads/2026/01/IICC2026-vignette2.jpg3600.0 s53.5 KiB
/wp-content/uploads/2021/09/vignette-brief-series-publica...3600.0 s50.8 KiB
www.iarc.who.int/wp-content/uploads/2023/02/infographics-photo-card.jpg3600.0 s50.1 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/fonts/Object-Sans-400.woff0.0 ms33.5 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/new-design.css3600.0 s41.5 KiB
www.iarc.who.int/wp-includes/js/jquery/jquery.js?ver=1.12.4-wp3600.0 s39.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/swiper.min.js?ver=5.3.23600.0 s39.0 KiB
/wp-content/themes/iarc-theme-new/js/jquery-3.3.1.min.js?...3600.0 s35.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/base-new.css3600.0 s34.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/custom-new.js3600.0 s30.4 KiB
/wp-content/themes/iarc-theme-new/css/bootstrap.min.css?v...3600.0 s27.8 KiB
www.iarc.who.int/wp-content/uploads/2023/02/ibb-collections.jpeg3600.0 s27.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/logo-white.svg3600.0 s21.1 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/logo.svg3600.0 s21.1 KiB
www.iarc.who.int/wp-content/uploads/2026/04/Vignette_journal-JNCI-MONOGRAPHS.jpg3600.0 s20.6 KiB
www.iarc.who.int/wp-content/uploads/2023/02/graphic-sample.jpg3600.0 s20.5 KiB
www.google-analytics.com/analytics.js7200.0 s20.9 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/bootstrap.min.js?ver=5.3.23600.0 s16.2 KiB
/wp-content/themes/iarc-theme-new/js/mCustomScrollbar.min...3600.0 s14.1 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/slick.min.js?ver=5.3.23600.0 s13.4 KiB
/wp-content/themes/iarc-theme-new/images/layout/instagram...3600.0 s9.9 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/tether.min.js?ver=5.3.23600.0 s8.9 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/chosen.min.js?ver=5.3.23600.0 s8.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/popper.min.js?ver=5.3.23600.0 s8.0 KiB
/wp-content/themes/iarc-theme-new/js/cookieconsent.min.js...3600.0 s7.9 KiB
www.iarc.who.int/wp-includes/css/dist/block-library/style.min.css?ver=5.3.23600.0 s7.8 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/responsive.css3600.0 s7.8 KiB
/wp-content/themes/iarc-theme-new/images/layout/iarc-web-...3600.0 s7.4 KiB
/wp-content/themes/iarc-theme-new/images/layout/bg-misc-p...3600.0 s7.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/fonts/icomoon.ttf0.0 ms5.8 KiB
/wp-content/themes/iarc-theme-new/images/layout/bg-misc-p...3600.0 s7.1 KiB
/wp-content/themes/iarc-theme-new/images/layout/facebook-...3600.0 s7.0 KiB
/wp-content/themes/iarc-theme-new/css/mCustomScrollbar.mi...3600.0 s5.8 KiB
/wp-content/themes/iarc-theme-new/images/layout/youtube-r...3600.0 s5.6 KiB
www.iarc.who.int/wp-includes/js/wp-emoji-release.min.js?ver=5.3.23600.0 s5.5 KiB
/wp-content/themes/iarc-theme-new/images/layout/linkedin-...3600.0 s5.1 KiB
www.iarc.who.int/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.4.13600.0 s4.6 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/iarc-web-tv.svg3600.0 s4.5 KiB
/wp-content/themes/iarc-theme-new/js/simple-lightbox.min....3600.0 s4.1 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/swiper.min.css?ver=5.3.23600.0 s4.0 KiB
/wp-content/themes/iarc-theme-new/images/layout/twitter-r...3600.0 s3.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/chosen.css?ver=5.3.23600.0 s3.4 KiB
/wp-content/plugins/google-analytics-dashboard-for-wp/ass...3600.0 s3.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/instagram.svg3600.0 s3.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/header-vertical.css3600.0 s2.7 KiB
/wp-content/themes/iarc-theme-new/css/cookieconsent.min.c...3600.0 s2.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/print-blue.svg3600.0 s2.2 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/header-home-page.css3600.0 s1.6 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/navigation.js?ver=201512153600.0 s1.6 KiB
/wp-content/themes/iarc-theme-new/images/layout/round-bg-...3600.0 s1.5 KiB
/wp-content/themes/iarc-theme-new/images/layout/round-bg-...3600.0 s1.5 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/youtube-blue.svg3600.0 s1.5 KiB
/wp-content/themes/iarc-theme-new/images/layout/linkedin-...3600.0 s1.5 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/youtube.svg3600.0 s1.5 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/linkedin.svg3600.0 s1.5 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/slick-theme.css?ver=5.3.23600.0 s1.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/print.css3600.0 s1.4 KiB
/wp-content/themes/iarc-theme-new/css/simplelightbox.min....3600.0 s1.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/rss-blue.svg3600.0 s1.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/rss.svg3600.0 s1.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/print.svg3600.0 s1.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/bg-filter.png3600.0 s1.2 KiB
www.iarc.who.int/wp-includes/js/wp-embed.min.js?ver=5.3.23600.0 s1.2 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/icomoon.css?ver=5.3.23600.0 s1.1 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/slick.css?ver=5.3.23600.0 s1.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/facebook.svg3600.0 s1020 B
/wp-content/themes/iarc-theme-new/images/layout/arrow-up-...3600.0 s969 B
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/twitter-blue.svg3600.0 s917 B
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/twitter.svg3600.0 s913 B
/wp-content/themes/iarc-theme-new/js/skip-link-focus-fix....3600.0 s869 B
www.iarc.who.int/wp-content/uploads/2023/02/doc.svg3600.0 s826 B
www.iarc.who.int/wp-content/themes/iarc-theme-new/style.css?ver=5.3.23600.0 s667 B
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/link-arrow.svg3600.0 s649 B
/wp-content/themes/iarc-theme-new/images/layout/bg-cards-...3600.0 s585 B

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLEst Savings
www.iarc.who.int/wp-content/themes/iarc-theme-new/fonts/icomoon.ttf1.2 s

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-IMG
nodeLabel: div.carousel-inner > a.clickable-card-link > div.image-container > img.d-block
path: 1,HTML,1,BODY,7,MAIN,0,DIV,1,DIV,0,A,0,DIV,0,IMG
selector: div.carousel-inner > a.clickable-card-link > div.image-container > img.d-block
snippet: <img class="d-block w-100 h-100" src="https://www.iarc.who.int/wp-content/uploads/2026/03/Banner_homepage-World-…" alt="">

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
value: no origins were preconnected
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

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
div.card-34 > a.clickable-card-link > div.card-34-content-img > img div.card-34 > a.clickable-card-link > div.card-34-content-img > img
www.iarc.who.int/wp-content/uploads/2025/07/pr368_vignette.jpg85.3 KiB74.4 KiB
div.card-34 > a.clickable-card-link > div.card-34-content-img > img div.card-34 > a.clickable-card-link > div.card-34-content-img > img
www.iarc.who.int/wp-content/uploads/2026/03/vignette-pr378-ECAC5.jpg85.0 KiB74.0 KiB
div.card-34 > a.clickable-card-link > div.card-34-content-img > img div.card-34 > a.clickable-card-link > div.card-34-content-img > img
www.iarc.who.int/wp-content/uploads/2026/01/WCD2026-vignette02.jpg79.9 KiB68.9 KiB
div.card-news > a.clickable-card-link > div.card-news-content-img > img div.card-news > a.clickable-card-link > div.card-news-content-img > img
/wp-content/uploads/2026/03/vignette_featured-news-world-...76.1 KiB65.2 KiB
div.card-news > a.clickable-card-link > div.card-news-content-img > img div.card-news > a.clickable-card-link > div.card-news-content-img > img
www.iarc.who.int/wp-content/uploads/2026/04/world-healthday-iarc-oms.jpg73.3 KiB62.3 KiB
div.rect-photo-card > a.rect-photo-card-content > div.rect-photo-card-content-img > img div.rect-photo-card > a.rect-photo-card-content > div.rect-photo-card-content-img > img
www.iarc.who.int/wp-content/uploads/2024/07/recent-covers-monographs.jpg71.2 KiB58.7 KiB
div.rect-photo-card > a.rect-photo-card-content > div.rect-photo-card-content-img > img div.rect-photo-card > a.rect-photo-card-content > div.rect-photo-card-content-img > img
www.iarc.who.int/wp-content/uploads/2023/02/GCO-vignette-homepage.jpg67.3 KiB55.5 KiB
div.card-news > a.clickable-card-link > div.card-news-content-img > img div.card-news > a.clickable-card-link > div.card-news-content-img > img
www.iarc.who.int/wp-content/uploads/2026/04/biobankIARC-2026-vignette.jpg61.4 KiB50.5 KiB
div.card-news > a.clickable-card-link > div.card-news-content-img > img div.card-news > a.clickable-card-link > div.card-news-content-img > img
www.iarc.who.int/wp-content/uploads/2025/09/ESB6-Vignette_op1.jpg58.4 KiB46.9 KiB
div.rect-photo-card > a.rect-photo-card-content > div.rect-photo-card-content-img > img div.rect-photo-card > a.rect-photo-card-content > div.rect-photo-card-content-img > img
www.iarc.who.int/wp-content/uploads/2023/02/newsletter-photo-card-web.jpg53.6 KiB44.2 KiB
div.card-news > a.clickable-card-link > div.card-news-content-img > img div.card-news > a.clickable-card-link > div.card-news-content-img > img
www.iarc.who.int/wp-content/uploads/2026/03/vignette-featurednews-mono141.jpg54.2 KiB43.2 KiB
div.card-news > a.clickable-card-link > div.card-news-content-img > img div.card-news > a.clickable-card-link > div.card-news-content-img > img
www.iarc.who.int/wp-content/uploads/2026/01/IICC2026-vignette2.jpg53.0 KiB42.1 KiB
div.card-news > a.clickable-card-link > div.card-news-content-img > img div.card-news > a.clickable-card-link > div.card-news-content-img > img
www.iarc.who.int/wp-content/uploads/2026/04/Vignette_journal-JNCI-MONOGRAPHS.jpg20.1 KiB10.3 KiB

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.

URLTransfer Size
www.iarc.who.int/wp-includes/js/jquery/jquery.js?ver=1.12.4-wp39.0 KiB
www.iarc.who.int/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.4.14.6 KiB
/wp-content/themes/iarc-theme-new/css/bootstrap.min.css?v...27.8 KiB
www.iarc.who.int/wp-includes/css/dist/block-library/style.min.css?ver=5.3.27.8 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/swiper.min.css?ver=5.3.24.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/new-design.css41.5 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/icomoon.css?ver=5.3.21.1 KiB
/wp-content/themes/iarc-theme-new/css/cookieconsent.min.c...2.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/slick-theme.css?ver=5.3.21.4 KiB
/wp-content/themes/iarc-theme-new/css/simplelightbox.min....1.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/slick.css?ver=5.3.21.0 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/base-new.css34.0 KiB
/wp-content/plugins/google-analytics-dashboard-for-wp/ass...3.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/header-vertical.css2.7 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/css/chosen.css?ver=5.3.23.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/print.css1.4 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/style.css?ver=5.3.2667 B
www.iarc.who.int/wp-content/themes/iarc-theme-new/header-home-page.css1.6 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/responsive.css7.8 KiB
/wp-content/themes/iarc-theme-new/css/mCustomScrollbar.mi...5.8 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: 80 ms 91.4 KiB
URLTransfer SizeEst Savings
www.iarc.who.int/wp-content/themes/iarc-theme-new/new-design.css41.1 KiB35.8 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/base-new.css33.6 KiB30.2 KiB
/wp-content/themes/iarc-theme-new/css/bootstrap.min.css?v...27.4 KiB25.4 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

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 40 ms 199.5 KiB
URLTransfer SizeEst Savings
www.googletagmanager.com/gtm.js?id=GTM-PQ9TBQ4132.1 KiB73.2 KiB
www.googletagmanager.com/gtag/js?id=G-END57GKPMR157.4 KiB65.9 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/swiper.min.js?ver=5.3.238.5 KiB34.1 KiB
www.iarc.who.int/wp-includes/js/jquery/jquery.js?ver=1.12.4-wp38.5 KiB26.4 KiB

Minifying CSS files can reduce network payload sizes. Learn how to minify CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 16.1 KiB
URLTransfer SizeEst Savings
www.iarc.who.int/wp-content/themes/iarc-theme-new/base-new.css34.0 KiB8.8 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/new-design.css41.5 KiB5.3 KiB
www.iarc.who.int/wp-content/themes/iarc-theme-new/responsive.css7.8 KiB2.0 KiB

Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 9.1 KiB
URLTransfer SizeEst Savings
www.iarc.who.int/wp-content/themes/iarc-theme-new/js/custom-new.js29.9 KiB9.1 KiB

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLTransfer Size
www.iarc.who.int/wp-content/uploads/2026/03/homepage_banner_141.jpg159.5 KiB
www.googletagmanager.com/gtag/js?id=G-END57GKPMR157.7 KiB
/wp-content/uploads/2026/03/Banner_homepage-World-Health-...138.2 KiB
www.googletagmanager.com/gtm.js?id=GTM-PQ9TBQ4132.2 KiB
www.iarc.who.int/wp-content/uploads/2026/02/cytoST_IARC-homepage.jpg118.8 KiB
www.iarc.who.int/wp-content/uploads/2026/01/Homepage_banner-IICC2026.jpg103.9 KiB
www.iarc.who.int/wp-content/uploads/2023/02/homepage-research-websites.jpg97.6 KiB
www.iarc.who.int/wp-content/uploads/2025/07/pr368_vignette.jpg85.9 KiB
www.iarc.who.int/wp-content/uploads/2026/03/vignette-pr378-ECAC5.jpg85.5 KiB
www.iarc.who.int/wp-content/uploads/2023/02/mono-handbooks-poster.jpg83.8 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
International Agency for Research on Cancer. World Health Organisation div.d-flex > div.header-logo > a.logo-link > img
www.iarc.who.int/wp-content/themes/iarc-theme-new/images/layout/logo.svg
twitter div.row > div.col-12 > a.social-icons-block-item > img.twitter
youtube div.row > div.col-12 > a.social-icons-block-item > img.youtube
linkedin div.row > div.col-12 > a.social-icons-block-item > img.linkedin
rss div.row > div.col-12 > a.social-icons-block-item > img.rss
print div.row > div.col-12 > a.social-icons-block-item > img.print
twitter div#mCSB_1 > div#mCSB_1_container > a.social-icons-block-item > img.twitter
youtube div#mCSB_1 > div#mCSB_1_container > a.social-icons-block-item > img.youtube
linkedin div#mCSB_1 > div#mCSB_1_container > a.social-icons-block-item > img.linkedin
facebook div#mCSB_1 > div#mCSB_1_container > a.social-icons-block-item > img.facebook
instagram div#mCSB_1 > div#mCSB_1_container > a.social-icons-block-item > img.instagram
tv div#mCSB_1 > div#mCSB_1_container > a.social-icons-block-item > img.tv
twitter div.d-flex > div.footer-top-content-links > a.social-icons-block-item > img.twitter
youtube div.d-flex > div.footer-top-content-links > a.social-icons-block-item > img.youtube
linkedin div.d-flex > div.footer-top-content-links > a.social-icons-block-item > img.linkedin
facebook div.d-flex > div.footer-top-content-links > a.social-icons-block-item > img.facebook
instagram div.d-flex > div.footer-top-content-links > a.social-icons-block-item > img.instagram
tv div.d-flex > div.footer-top-content-links > a.social-icons-block-item > img.tv
up div.container-fluid > div.footer-menu-row > div.footer-arrow > img

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

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 261 ms
URLTime Spent
iarc.fr/261 ms
www.iarc.who.int/0.0 ms
●Time to Interactive 2.4 s
●Layout shift culprits
●Optimize DOM size
●Forced reflow
●LCP breakdown
●Modern HTTP
●Optimize viewport for mobile
●Max Potential First Input Delay 40 ms
●User Timing marks and measures 5 user timings
●JavaScript execution time 0.2 s
●Minimizes main-thread work 0.7 s
●Page didn't prevent back/forward cache restoration
●Network Requests
●Network Round Trip Times 20 ms
●Server Backend Latencies 1,120 ms
●Tasks
●Diagnostics
●Metrics
●Screenshot Thumbnails
●Final Screenshot
●Script Treemap Data
●Resources Summary
●Initial server response time was short Root document took 460 ms
●Avoid large layout shifts 1 layout shift found
○INP breakdown
○Avoid long main-thread tasks
○Avoid non-composited animations
75

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.

Names and labels

When a button doesn't have an accessible name, screen readers announce it as "button", making it unusable for users who rely on screen readers. Learn how to make buttons more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
main#main > div#banner > ol.carousel-indicators > button#play-button main#main > div#banner > ol.carousel-indicators > button#play-button
div.row > div.carousel-rect > div#carousel-manual69e92d91c1df1 > button#play-card-carousel-button div.row > div.carousel-rect > div#carousel-manual69e92d91c1df1 > button#play-card-carousel-button

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
main#main > div#banner > div.carousel-inner > a.clickable-card-link main#main > div#banner > div.carousel-inner > a.clickable-card-link
div#carousel-manual69e92d91c1df1 > div.carousel-inner > div.carousel-item > a.clickable-card-link div#carousel-manual69e92d91c1df1 > div.carousel-inner > div.carousel-item > a.clickable-card-link

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Contrast

Low-contrast text is difficult or impossible for many users to read. Learn how to provide sufficient color contrast.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
CONTINUE div.custom-layout-row > div.custom-layout > div.cc-compliance > a.cc-btn

These are opportunities to improve the legibility of your content.

Tables and lists

Screen readers have a specific way of announcing lists. Ensuring proper list structure aids screen reader output. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
1 2 3 4 body.home > main#main > div#banner > ol.carousel-indicators
21 Apr 2026 Premenopausal and postmenopausal obesity and endometrial cancer ris… div.row > div.just-published > div.just-published-content > ul.articles-list

Screen readers require list items (`<li>`) to be contained within a parent `<ul>`, `<ol>` or `<menu>` to be announced properly. Learn more about proper list structure.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
21 Apr 2026 Premenopausal and postmenopausal obesity and endometrial cancer ris… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
21 Apr 2026 Risk of Head and Neck Cancer in Former Smokers by Subsite: A Multic… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
21 Apr 2026 World Health Organization classification of tumours of the breast 6… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
17 Apr 2026 Occupational exposure to chlorinated solvents and lung cancer: resu… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
16 Apr 2026 Accelerating discovery of cancer causes for prevention in the era o… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
16 Apr 2026 Systematic review and meta-analysis of cervico-vaginal high-risk hu… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
16 Apr 2026 Genetic predisposition to high BMI, ultra-processed food consumptio… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
15 Apr 2026 Understanding age and sex differentials in cancer incidence and mor… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
15 Apr 2026 Human papillomavirus infection and vaccination among young females … ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article
10 Apr 2026 Author's Response to the Commentary by Raitoharju E et al. on "Epig… ul.articles-list > div#mCSB_2 > div#mCSB_2_container > li.article

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

Best practices

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more about the viewport meta tag.

Why this matters

Informational: a Permissions-Policy directive showing feature -> allowed origins.

Source: MDN Permissions-Policy

Failing Elements
head > meta head > meta

These items highlight common accessibility best practices.

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
Privacy policy div.custom-layout-row > div.custom-layout > span#cookieconsent:desc > a.cc-link
CONTINUE div.custom-layout-row > div.custom-layout > div.cc-compliance > a.cc-btn
○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
●Image elements have `[alt]` attributes
●`button`, `link`, and `menuitem` elements have accessible names
●ARIA attributes are used as specified for the element's role
●Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
●`[aria-hidden="true"]` elements do not contain focusable descendents
●Elements use only permitted ARIA attributes
●Document has a `<title>` element
●`<html>` element has a `[lang]` attribute
●`<html>` element has a valid value for its `[lang]` attribute
●No element has a `[tabindex]` value greater than 0
●Touch targets have sufficient size and spacing.
●Heading elements appear in a sequentially-descending order
●Document has a main landmark.
●Deprecated ARIA roles were not used
●ARIA IDs are unique
●Identical links have the same purpose.
○`[accesskey]` values are unique
○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
○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
○Form elements have associated labels
○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.
○Skip links are focusable.
○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
●Use a strong HSTS policy
●Ensure proper origin isolation with COOP
●Mitigate clickjacking with XFO or CSP
●Mitigate DOM-based XSS with Trusted Types
●Detected JavaScript libraries
●Page has valid source maps
○Redirects HTTP traffic to HTTPS
92

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.

Content Best Practices

Meta descriptions may be included in search results to concisely summarize page content. Learn more about the meta description.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Format your HTML in a way that enables crawlers to better understand your app’s content.

○Structured data is valid
●Page isn’t blocked from indexing
●Document has a `<title>` element
●Page has successful HTTP status code
●Links have descriptive text
●Links are crawlable
●robots.txt is valid
●Image elements have `[alt]` attributes
●Document has a valid `hreflang`
○Document has a valid `rel=canonical`

Send Feedback