Meanings of less efficacious in English

Why are these compositions less efficacious than those of the barbarian Medea?

It is a hidden influence, but not the less efficacious.

For Baptism which bestows full remission of sins is not less efficacious than this sacrament.

The following case was far more severe, but the mode of treatment was not less efficacious.

At night she had recourse to the little bottle, but this time it was less efficacious.

Different methods may be more or less efficacious in different places; it is a matter for legitimate opportunism.

But you should report to your superiors that, in Riordan's case, my abilities will be less efficacious now.

But at the same time it cannot be denied that these would only be palliatives, more or less efficacious.

Quite true, my dear,-butthat does not make the words out of her mouth the less efficacious for evil.

I have believed since that if He had suffered in any other nature, His suffering would be no less efficacious.

Interpretation: FSPT is safe and no less efficacious than IEPT for treatment of moderate-to-severe neonatal hyperbilirubinaemia in near-term and term infants.

With current therapies becoming less efficacious due to increased drug resistance, new inhibitors of both bacterial and malarial targets are desperately needed.

Theories and notions, in all their varieties of truth and falsehood, are a machinery more or less efficacious, directed to the same end.

But, sir, there is one motive to moderation that has seldom been found less efficacious than the consideration of the laws of justice or humanity.

That which cannot be done with the magical aid of machinery, must be attempted by less ambitious, and we fear by far less efficacious means.

"It were best to leave them in place but render them less efficacious," replied the puppet sorcerer.