After some digging it goes back to Adriaan de Groot (in 1946).

[1] (2011) has a summary in the introduction:

   de Groot presented chess players of varying skill, including some of the best players of the time, with an unfamiliar position and asked them to think aloud as they analyzed the position and chose what move they would make. de Groot found that, contrary to popular belief, the strongest players did not think further ahead than weaker players. World-class Grandmasters (GMs) searched at a similar depth and considered a similar number of options as mere chess experts.

As [1] is also a somewhat reproduction of the original study, you can take it directly.

    Six Grandmasters, five International Masters, six Experts, and five Class A players completed the think-aloud procedure for two chess positions. Findings indicate that Grandmasters and International Masters search more quickly than Experts and Class A players, and that both groups today search substantially faster than players in previous studies. The findings, however, support de Groot’s overall conclusions and are consistent with predictions made by pattern recognition models.

Section 3 Table 2 is probably most interesting, they had 2 board positions and 2 groups sectioned:

Masters (2350+) | Intermediates (1800-2200)

(Mean values only, i tried inlcuding stddev but it was hard to read)

Positions Evaluated (A): 145.3 | 138.6

Positions Evaluated (B): 216.6 | 190.6

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Max Depth (A): 11.7 | 9.4

Max Depth (B): 14.1 | 12.0

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Mean Depth (A): 4.1 | 3.3

Mean Depth (B): 4.9 | 4.2

What i found interesting was that the "intermediate" group had a higher number of "base moves" they evaluated (eg Pos A: 5.6 | 8.6).

The previous studies (de Groot and another rperoduction from 1998) had "Nodes visited" for position A at 51.6 | 34.3 and 48.3 | 40.1 so similarly close together as the new ones, but much lower. (depending on your definition on "similarly close together")

[1] https://onlinelibrary.wiley.com/doi/10.1111/j.1551-6709.2011...

Could a modern chess engine on a Pentium have defeated Kasparov in 1996?