The phrase "a slightly more effective" is correct and usable in written English.
It can be used when comparing the effectiveness of two or more things, indicating a small improvement in effectiveness.
Example: "This new marketing strategy is a slightly more effective approach than our previous one."
Alternatives: "somewhat more effective" or "a bit more effective".
With luck, a slightly more effective, more self-disciplined parliament.
The Broncos, with a slightly more effective defense, and a far superior running game, are at home and will look to end the Saints' modest two-game winning streak.
He did add that the National Guard can survey the landscape from helicopters, which is a slightly more effective way to spot border crossers.
Corresponding data for different sweep gas flows were comparable, where a higher sweep gas flow of 16 L/minute resulted in only a slightly more effective ECCO2R compared to a lower sweep gas flow of 8 L/minute (Tables 2 and 3 and Additional file 1).
The acid solutions (with solid solutes) all displayed similar effectiveness, and were all slightly more effective, on a per mole basis, than the DMMP solution (a liquid solute).
SP-A is slightly more effective than SP-D at neutralizing nonglycosylated IAV strains, and it neutralizes IAV strains resistant to SP-D [ 12].
If clean non-coated catheters are not considered a relevant option, gel reservoir catheters are slightly more effective than hydrophilic with a small additional cost and an incremental cost effectiveness ratio of about £3000 per QALY.
Placebo injections often work better than placebo pills (at least in the US, where "shots" are often seen as a stronger treatment – in Europe placebo pills are slightly more effective), while stopping a placebo treatment often creates withdrawal symptoms.
This is consistent with another study which showed that telephone reminders by a staff member were also slightly more effective than automated phone calls to reduce non-attendance in an academic outpatient practice [ 13].
Last month, the company said a study had shown that Vanlev, a heart drug that the company had expected to be its next blockbuster, was only slightly more effective than a drug already available in a low-priced generic form.
Topical betamethasone dipropinate, a corticosteroid, was demonstrated to be slightly more effective than calcitriol 3 μg g−1 ointment but a higher proportion of responders treated with the latter drug remained in remission over the next eight weeks.
