Table 5.
A List of All Known Problems Detected by AChecker at Level A, Sorted from The Most Recurring to The Least
| Category | Guideline | Success criteria | Websites affected | Error frequency | Error percentage % |
|---|---|---|---|---|---|
| Perceivable | 1.1 |
Img element missing alt attribute Success Criteria 1.1.1 Non-text Content |
9 | 85 | 25.84 |
| Operable | 2.4 |
Anchor contains no text Success Criteria 2.4.4 Link Purpose (In Context) |
6 | 81 | 24.62 |
| Perceivable | 1.1 |
Image used as anchor is missing valid Alt text Success Criteria 1.1.1 Non-text Content |
7 | 76 | 23.10 |
| Understandable | 3.3 |
Label text is empty Success Criteria 3.3.2 Labels or Instructions |
5 | 18 | 5.47 |
| Perceivable | 1.3 |
input element, type of "text", missing an associated label Success Criteria 1.3.1 Info and Relationships |
5 | 11 | 3.34 |
| Perceivable | 1.3 |
Input element, type of "text", has no text in label Success Criteria 1.3.1 Info and Relationships |
5 | 11 | 3.34 |
| Understandable | 3.1 |
Document language not identified Success Criteria 3.1.1 Language of Page |
4 | 10 | 3.04 |
| Understandable | 3.1 |
Document has invalid language code Success Criteria 3.1.1 Language of Page |
4 | 10 | 3.04 |
| Robust | 4.1 |
Id attribute is not unique Success Criteria 4.1.1 Parsing |
4 | 5 | 1.52 |
| Operable | 2.4 |
title element is empty Success Criteria 2.4.2 Page Titled |
1 | 5 | 1.52 |
| Operable | 2.1 |
onmousedown event missing onkeydown event Success Criteria 2.1.1 Keyboard |
0 | 3 | 0.91 |
| Perceivable | 1.1 |
input element has alt attribute Success Criteria 1.1.1 Non-text Content |
1 | 2 | 0.61 |
| Operable | 2.4 |
Document missing title element Success Criteria 2.4.2 Page Titled |
1 | 2 | 0.61 |
| Perceivable | 1.3 |
textarea element missing an associated label Success Criteria 1.3.1 Info and Relationships |
2 | 2 | 0.61 |
| Perceivable | 1.1 |
embed element missing noembed element Success Criteria 1.1.1 Non-text Content |
1 | 1 | 0.30 |
| Perceivable | 1.3 |
Input element, type of "password", missing an associated label Success Criteria 1.3.1 Info and Relationships |
1 | 1 | 0.30 |
| Perceivable | 1.3 |
Input element, type of "checkbox", missing an associated label Success Criteria 1.3.1 Info and Relationships |
1 | 1 | 0.30 |
| Perceivable | 1.3 |
Input element, type of "checkbox", has no text in label Success Criteria 1.3.1 Info and Relationships |
1 | 1 | 0.30 |
| Perceivable | 1.3 |
Input element, type of "password", has no text in label Success Criteria 1.3.1 Info and Relationships |
1 | 1 | 0.30 |
| Operable | 2.1 |
Script not keyboard accessible—onmouseout missing onblur Success Criteria 2.1.1 Keyboard |
1 | 1 | 0.30 |
| Operable | 2.1 |
Onmouseover event handler missing onfocus event handler Success Criteria 2.1.1 Keyboard |
1 | 1 | 0.30 |
| Understandable | 3.1 |
Right to left reading order not marked or marked incorrectly Success Criteria 3.1.1 Language of Page |
1 | 1 | 0.30 |
| Total | 329 | 100 |