'all indicate that' is correct and usable in written English.
You can use it to connect a group of details, observations, or facts that together support a particular conclusion or lead to a specific inference. For example: The sudden drop in sales, the negative customer feedback, and the increase in product returns all indicate that the new design is not resonating well with consumers.
The results of the multiple analyses all indicate that P. nobilis throughout the Mediterranean comprises one lineage that underwent a recent population expansion from a single original population with low effective population size, as hypothesized by18.
All indicate that this design has very good prospects for development.
These results all indicate that the phosphorylated TTG1 at Ser 215 is unable to interact with TT2.
These characteristics all indicate that the soil, which began to form in late Holocene time, is not well developed.
There are standard combinations, "slave of the merciful one", "slave of the generous one", etc, which all indicate that the person is a servant of God.
Declining stock prices, falling commodity prices, and increased volatility all indicate that there may be something deeper threatening global growth.
Both the raw and adjusted ACORN-SAT data and the larger unadjusted national data set all indicate that Australian air temperatures have warmed over the last century.
* Previous studies, some recent, all indicate that with rare exceptions seat belts alone can and do prevent many injuries and deaths.
Yet friends of Mr. Volcker, Mr. Whitehead and Mr. Wriston all indicate that their candidates' refusal was not definitive and that they might still be persuaded.
The language in Safari'spreferences menu, Apple's promotional materials, and developer discussions all indicate that advertising-related tracking was a central motivation for the cookie blocking feature.
A growth in the population, major construction projects, a significant expansion in arts and culture, all indicate that society is prosperous.
