The phrase 'a worthwhile improvement' is correct and usable in written English.
You can use this phrase to refer to something that has been changed or improved in a meaningful way. For example, "The newly designed air filters offer a worthwhile improvement in air quality."
However, you may need a mid-range card to see a worthwhile improvement.
The pace of trade liberalisation and deregulation, which helped productivity growth in the 1990s, has also slowed, if it has not reversed.If labour productivity growth in the non-farm business sector is 2%, that would still be a worthwhile improvement on previous decades.
Notably the BER reduction for SNR = 20 dB is of an order of a magnitude which consists of a worthwhile improvement for this small scale MIMO system.
Performance testing on the Buffalo bridges revealed no outstanding issues, but prolonged testing showed that upgrading to 802.11n provides a worthwhile improvement for frame rates.
This was a subjective estimate of the percentage increase that might represent a worthwhile improvement when offset against anticipated decline in precision.
One hundred and thirty-five (79%) patients became seizure free (Engel 1), 18 (11%) patients showed rare disabling seizures (Engel 2), 14 (8%) patients had a worthwhile improvement (Engel 3) and four (2%) patients did not change (Engel 4).
Finally, RK gave a modest but worthwhile improvement in performance over OK in this study, especially at scales of most interest (Fig. 4).
With locoregionally applied IL-2 a modest but clinically worthwhile improvement was obtained in six out of 16 patients; remarkably these six all belonged to the group of seven patients that were treated with intratumoral IL-2.
Most of the biologic agents do better if combined with conventional immunosuppressive DMARDs and they show a similar efficacy profile: most of the responders achieve the minimum desirable level of response (ACR20) and only few patients obtain a worthwhile clinical improvement (ACR70 or better).
In short, any 'signal' would be lost in 'noise'; a false null result would be likely even if worthwhile improvement had occurred.
In fact, of the 338 patients who experienced any seizure recurrence, 163 (48%) were seizure-free by last follow-up (Engel I), 78 (23%) were significantly improved (Engel II), 672020%) had no worthwhile improvement (Engel III) and 30 (9%) were worse off (Engel IV).
