Lighthouse Mobile
· 0 checks — Mobile Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.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.
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
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.
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.
Performance issues directly impact user engagement and conversion rates.
Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.
Performance issues directly impact user engagement and conversion rates.
Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.
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.
Performance issues directly impact user engagement and conversion rates.
Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size
Performance issues directly impact user engagement and conversion rates.
| URL | Resource Size | Est Savings | |
|---|---|---|---|
Main Banner Image div.slideshow-container > div.mySlides > a > img | www.cochranelibrary.com/image/journal/article?img_id=488500349&t=1776690427734 | 55.9 KiB | 37.6 KiB |
Multiple article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670274&t=1774877752172 | 36.2 KiB | 27.7 KiB |
Maternal, article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670272&t=1774877752093 | 32.6 KiB | 24.9 KiB |
Climate article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670278&t=1774877752328 | 27.0 KiB | 20.6 KiB |
Infectious article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670276&t=1774877752253 | 20.4 KiB | 15.6 KiB |
Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
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.
Performance issues directly impact user engagement and conversion rates.
These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.
Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.
Performance issues directly impact user engagement and conversion rates.
| URL | Time Spent |
|---|---|
| cochranelibrary.com/ | 928 ms |
| www.cochranelibrary.com/ | 802 ms |
| www.cochranelibrary.com/?cookiesEnabled | 0.0 ms |
| www.cochranelibrary.com/ | 0.0 ms |
These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS
Performance issues directly impact user engagement and conversion rates.
| Element | Layout shift score |
|---|---|
Scientific Strategy
Maternal, newborn and child health
Multiple chronic conditi… div.homepage-upper-content-wrapper > div#homepage-upper-content > div#layout-column_homepage-upper-content > div#p_p_id_56_INSTANCE_z9ZXcO5iSFG5_ | 0.422 |
Multiple chronic conditions div.journal-content-article > div.mini-hero-section > section.mini-hero-wrapper > article.mini-hero | 0.363 |
Scientific Strategy
Maternal, newborn and child health
Multiple chronic conditi… div.homepage-upper-content-wrapper > div#homepage-upper-content > div#layout-column_homepage-upper-content > div#p_p_id_56_INSTANCE_z9ZXcO5iSFG5_ | 0.110 |
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.
Performance issues directly impact user engagement and conversion rates.
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.
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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| /cochrane-theme/css/custom.css?browserId=other&themeId=co... | 93.3 KiB | 88.8 KiB |
| /html/css/main.css?browserId=other&themeId=cochrane_WAR_c... | 20.1 KiB | 20.0 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.
Performance issues directly impact user engagement and conversion rates.
| URL | Transfer Size | Est Savings |
|---|---|---|
| www.cochranelibrary.com/cochrane-theme/js/theme.js?t=1776315578000 | 174.0 KiB | 113.3 KiB |
| www.googletagmanager.com/gtag/js?id=G-BRLBHKT9XF&l=gDataLayer&cx=c>m=4e64k0 | 144.7 KiB | 69.1 KiB |
| /html/js/barebone.jsp?browserId=other&themeId=cochrane_WA... | 121.6 KiB | 66.7 KiB |
| www.googletagmanager.com/gtag/js?id=UA-189672-63&l=gDataLayer | 124.9 KiB | 63.9 KiB |
| assets.adobedtm.com/59640f9fa510/7cad07cf7779/launch-a215d9c51521.min.js | 59.8 KiB | 25.1 KiB |
| cmp.osano.com/AzZdRbSORDOOzF9W/d594efc1-9663-477d-9528-6576640e64fd/osano.js | 63.4 KiB | 22.2 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.
Performance issues directly impact user engagement and conversion rates.
| URL | Total CPU Time | Script Evaluation | Script Parse |
|---|---|---|---|
| www.cochranelibrary.com/ | 1.0 s | 129 ms | 11 ms |
| cmp.osano.com/AzZdRbSORDOOzF9W/d594efc1-9663-477d-9528-6576640e64fd/osano.js | 884 ms | 763 ms | 21 ms |
| Unattributable | 682 ms | 88 ms | 0.0 ms |
| www.cochranelibrary.com/cochrane-theme/js/theme.js?t=1776315578000 | 530 ms | 401 ms | 62 ms |
| assets.adobedtm.com/59640f9fa510/7cad07cf7779/launch-a215d9c51521.min.js | 248 ms | 196 ms | 22 ms |
| www.cochranelibrary.com/cdn-cgi/challenge-platform/scripts/jsd/main.js | 235 ms | 224 ms | 3.3 ms |
| /html/js/barebone.jsp?browserId=other&themeId=cochrane_WA... | 163 ms | 116 ms | 35 ms |
| www.googletagmanager.com/gtag/js?id=G-BRLBHKT9XF&l=gDataLayer&cx=c>m=4e64k0 | 149 ms | 114 ms | 35 ms |
| www.googletagmanager.com/gtag/js?id=UA-189672-63&l=gDataLayer | 103 ms | 75 ms | 28 ms |
| injections.readcube.com/cochrane/epdf_linker.8c0d96d8.js | 78 ms | 45 ms | 4.5 ms |
| /extensions/EP31dbb9c60e404ba1aa6e746d49be6f29/AppMeasure... | 76 ms | 73 ms | 0.5 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
Performance issues directly impact user engagement and conversion rates.
| Category | Time Spent |
|---|---|
| Script Evaluation | 2.3 s |
| Other | 850 ms |
| Style & Layout | 531 ms |
| Script Parsing & Compilation | 256 ms |
| Parse HTML & CSS | 213 ms |
| Rendering | 72 ms |
| Garbage Collection | 68 ms |
Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache
Performance issues directly impact user engagement and conversion rates.
| Failure reason | Failure type |
|---|---|
| The page has an unload handler in the main frame. | Actionable |
| Pages with cache-control:no-store header cannot enter back/forward cache. | Actionable |
| Pages whose main resource has cache-control:no-store cannot enter back/forward cache. | Not actionable |
| Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header. | Not actionable |
Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions
Performance issues directly impact user engagement and conversion rates.
| URL | |
|---|---|
Maternal, article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670272&t=1774877752093 |
Multiple article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670274&t=1774877752172 |
Infectious article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670276&t=1774877752253 |
Climate article.mini-hero > a.mini-hero-module > div.mini-hero-image-wrapper > img.mini-hero-image | www.cochranelibrary.com/image/journal/article?img_id=486670278&t=1774877752328 |
Main Banner Image div.slideshow-container > div.mySlides > a > img | www.cochranelibrary.com/image/journal/article?img_id=488500349&t=1776690427734 |
Image 3 div.journal-content-article > div.external-link-row > a > img | www.cochranelibrary.com/cochrane-theme/images/external_links/our_journal.png |
Image 2 div.journal-content-article > div.external-link-row > a > img | www.cochranelibrary.com/cochrane-theme/images/external_links/our_evidence.png |
Image 4 div.journal-content-article > div.external-link-row > a > img | www.cochranelibrary.com/cochrane-theme/images/external_links/how_to_order.png |
Image 5 div.journal-content-article > div.external-link-row > a > img | www.cochranelibrary.com/cochrane-theme/images/external_links/our_products.png |
Image 1 div.journal-content-article > div.external-link-row > a > img | www.cochranelibrary.com/cochrane-theme/images/external_links/get_involved.png |
Cochrane Library logo div.branding > h1.brand-container > a > img.brand-logo | www.cochranelibrary.com/cochrane-theme/images/en-US_logo.png |
Stay connected with us article.alert-content-module > div.button-container > div.alert-module-image-wrapper > img | www.cochranelibrary.com/cochrane-theme/images/social/bell.png |
div.brand-content > div.logo-block > a > img.footer-logo div.brand-content > div.logo-block > a > img.footer-logo | www.cochranelibrary.com/cochrane-theme/images/footer-logo-part-2.png |
Wiley logo div.brand > div.brand-container > a > img.logo | www.cochranelibrary.com/cochrane-theme/images/en-US_wiley-footer-logo.png |
Cochrane logo div.brand-content > div.logo-block > a > img.footer-logo | www.cochranelibrary.com/cochrane-theme/images/footer-logo-part-1.png |
article.alert-content-module > div.button-container > a.alert-button > img article.alert-content-module > div.button-container > a.alert-button > img | www.cochranelibrary.com/cochrane-theme/images/social/bluesky-sm.svg |
More information about the performance of your application. These numbers don't directly affect the Performance score.
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.
Navigation
Properly ordered headings that do not skip levels convey the semantic structure of the page, making it easier to navigate and understand when using assistive technologies. Learn more about heading order.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
Stay connected with us article.alert-content-module > div.button-container > div.alert-module-image-wrapper > h4 |
These are opportunities to improve keyboard navigation in your application.
Names and labels
Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
article.alert-content-module > div.button-container > a.alert-button > img article.alert-content-module > div.button-container > a.alert-button > img |
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.
Best Practices
User Experience
Image display dimensions should match natural aspect ratio. Learn more about image aspect ratio.
Performance issues directly impact user engagement and conversion rates.
| URL | Aspect Ratio (Displayed) | Aspect Ratio (Actual) | |
|---|---|---|---|
Image 1 div.journal-content-article > div.dl-banner-container > div.dl-banner-block > img | www.cochranelibrary.com/cochrane-theme/images/beta-icon.png | 20 x 60 (0.33) | 44 x 105 (0.42) |
General
Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.
Performance issues directly impact user engagement and conversion rates.
| Deprecation / Warning | Source |
|---|---|
| Unload event listeners are deprecated and will be removed. | cmp.osano.com/AzZdRbSORDOOzF9W/d594efc1-9663-477d-9528-6576640e64fd/osano.js line 1, col 141321 |
| SharedStorage | |
| StorageType.persistent is deprecated. Please use standardized navigator.storage instead. | |
| Fledge |
Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. Learn more about this errors in console diagnostic audit
Performance issues directly impact user engagement and conversion rates.
| Source | Description |
|---|---|
Failed to load resource: the server responded with a status of 404 () | |
Failed to load resource: the server responded with a status of 404 () | |
Failed to load resource: the server responded with a status of 404 () | |
Refused to apply style from 'https://www.cochranelibrary.com/cochrane-theme/css/aui.css?browserId=other&themeId=cochrane_WAR_cochranetheme&minifierType=css&languageId=en_US&b=6210&t=1776315578000' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled. | |
Refused to apply style from 'https://www.cochranelibrary.com/cochrane-theme/css/aui.css?browserId=other&themeId=cochrane_WAR_cochranetheme&minifierType=css&languageId=en_US&b=6210&t=1776315578000' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled. | |
Refused to apply style from 'https://www.cochranelibrary.com/cochrane-theme/css/main.css?browserId=other&themeId=cochrane_WAR_cochranetheme&minifierType=css&languageId=en_US&b=6210&t=1776315578000' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled. | |
Refused to apply style from 'https://www.cochranelibrary.com/cochrane-theme/css/main.css?browserId=other&themeId=cochrane_WAR_cochranetheme&minifierType=css&languageId=en_US&b=6210&t=1776315578000' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled. | |
Refused to execute script from 'https://www.cochranelibrary.com/cochrane-theme/js/main.js?browserId=other&minifierType=js&languageId=en_US&b=6210&t=1776315578000' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled. | |
Refused to execute script from 'https://www.cochranelibrary.com/scolaris-content-display/js/topics-lookup.js?browserId=other&minifierType=js&languageId=en_US&b=6210&t=1776315622000' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled. |
Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. Learn more about source maps.
Performance issues directly impact user engagement and conversion rates.
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
Performance issues directly impact user engagement and conversion rates.
| Uncrawlable Link |
|---|
❮ div.portlet-body > div.journal-content-article > div.slideshow-container > a.prev |
❯ div.portlet-body > div.journal-content-article > div.slideshow-container > a.next |
To appear in search results, crawlers need access to your app.
Content Best Practices
Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.
Performance issues directly impact user engagement and conversion rates.
| Failing Elements |
|---|
article.alert-content-module > div.button-container > a.alert-button > img article.alert-content-module > div.button-container > a.alert-button > img |
Format your HTML in a way that enables crawlers to better understand your app’s content.