"If you hear advice from a grandmother or elders, odds are that it works at ninety percent. On the other hand, in part because of scientism and academic prostitution, in part because the world is hard, if you read anything by psychologists and behavioral scientists, odds are it works at less than ten percent, unless it is also what has been covered by the grandmother and the classics, in which case why would you need a nerd-psychologist?
"This may seem aggressive, but it flows directly from the Lindy Effect, partly from my own assessment of the statistical significance of the results, which is subjected to a Fooled by Randomness effect ... Consider that a recent effort to replicate the hundred psychology papers in 'prestigious' journals of 2008 found that, out of a hundred, only thirty nine replicated. Of these thirty nine, I believe than less than ten are actually robust and transfer outside the narrowness of the experiment. Similar defects have been found in medicine, neuroscience; on those later."
Source: Nassim Nicholas Taleb, An Expert Called Lindy