Michel Roland's Library tagged evans →  View Popular

What this suggests to me is that the driving force in Evans' suggested "narrow[ing of] the range of findings and ideas built upon" is not online access per se but in fact commercial access, with its attendant question of who can afford to read what.  Evans' own data indicate that if the online access in question is free of charge, the apparent narrowing effect is significantly reduced or even reversed.  Moreover, the commercially available corpus is and has always been much larger than the freely available body of knowledge (for instance, DOAJ currently lists around 3500 journals, approximately 10-15% of the total number of scholarly journals).  This indicates that if all of the online access that went into Evans' model had been free all along, the anti-narrowing effect of Open Access would be considerably amplified.

A great deal of work was done in the 1970s, which is now completely ignored. Researchers rediscover wheels again and again, when a search of the earlier literature would have revealed that what they think of as novel, was novel 50 years ago!

If I had to choose between the explanation of the Evans effect as a recency/bandwagon effect, as Evans interprets it, or as an increased overall quality/selectivity effect, I'd choose the latter (though I don't doubt there is a bandwagon effect too). And that is even without going on to point out that Tenopir & King, Gingras and others have shown that -- with or without OA -- there is still a good deal of usage and citation of the legacy literature (though it differs from field to field).



I wouldn't set much store by "skimming serendipity" (the discovery of adjacent work while skimming through print issues), since online search and retrieval has at least as much scope for serendipity. (And one would expect more likelihood of a bandwagon effect without OA, where authors may tend to cite already cited but inaccessible references "cite unseen.")