| Keyword | CPC | PCC | Volume | Score |
|---|---|---|---|---|
| how does an iron lung work | 1.55 | 0.7 | 786 | 76 |
| how does an iron lung work for polio patients | 0.64 | 0.2 | 2957 | 11 |
| how does an iron lung work for polio | 1.5 | 1 | 5519 | 51 |
| what is an iron lung and how does it work | 1.71 | 0.1 | 3258 | 60 |
| how does an iron lung machine work | 1.3 | 0.3 | 7932 | 78 |
| how did the iron lung work | 1.99 | 0.6 | 4273 | 47 |
| how an iron lung works | 0.42 | 0.5 | 7544 | 49 |
| was the iron lung used for polio | 1.59 | 0.5 | 8289 | 2 |
| iron lung treatment for polio | 0.68 | 0.6 | 7224 | 76 |
| polio and the iron lung | 0.23 | 0.5 | 9399 | 53 |
| iron lungs for polio machine | 1.36 | 0.7 | 8723 | 55 |
| polio disease iron lung | 0.47 | 0.8 | 8273 | 98 |
| polio and iron lung treatment | 1.34 | 0.3 | 8030 | 25 |
| polio ward iron lung | 1.16 | 1 | 2276 | 22 |
| polio iron lung machine | 0.73 | 0.7 | 6251 | 13 |
| paul polio iron lung | 1.27 | 0.6 | 8455 | 57 |
| polio man in iron lung | 0.48 | 0.2 | 7333 | 25 |
| polio survivor iron lung | 1.61 | 0.6 | 4875 | 72 |
| iron lung and polio victims | 0.32 | 0.6 | 297 | 35 |
| polio iron lung survivors | 1.33 | 0.6 | 6436 | 49 |
| polio ward iron lung image | 0.91 | 1 | 8466 | 25 |
