According to the epistemology, the image of a real appearance can be interpreted either as an complete and exact image or as a congruence of essential parts of the reality and its reflection.
The latter applies to the relationship between the quantity of  all research activities and the quantity of all publications.
Essential relations existing in the total quantity of research activities exist as comparable appearances in the publication frequencies.

Table 3 (see below)  illustrates these relationships by some typical examples.

The scientific reliability to look at the publication frequencies as the reflection of research activities increases with increasing quantity of document-descriptions which are available in the bibliographic online databases.
The maximum quantity of document descriptions would be achieved, if to a given theme the descriptions of all  scientific publications in the world  would be stored in the online databases.
At the present time it is not possible yet to recognize exactly, how many scientific docu- ments to a given theme in fact  have been published everywhere in the world.
However  the extraordinary sizes of representative online databases and  their stable growth rates since many years clearly indicate that the bibliographic databases inform about the most large portion of publications worldwide.

Hence the hypothesis is valid that the online available quantity of document descriptions in the tendency reflects the true publication process.
But basic condition is that the frequency analyses are based on searches in a database cluster linking the most representative databases for publication descriptions with reference to the given theme area as a virtual Super-Database.

The lower limit for the total quantity of document descriptions in those databases which are contained in the database-cluster depends on the defined analysis-theme.
The experience shows that in the present-time for analyses to the above-mentioned theme area ("Thin Organic Films") a number of forty millions document descriptions should be checkable.

It exist furthermore circumstances which influence the accuracy of the reflection of R?D activities in the publication frequencies. Such circumstances are:
- It is published too much.
- The publications are hidden.
- It is published not enough

"It is published too much" means: one and the same research-result is repeatedly publi- shed either in various media or in slightly modified form.
By means of automated publication-comparisons which are focussed on the content of the publications the most of these duplicates might be eliminated in future.

„The publications are hidden“ that means: the research results in such media were published which are not taken into consideration for acquisition of information because either these media are unknown or they have apparently a low significance or  their translation is too difficult (language barriers).
Hiddenly publishing stands also in connection with the questions of the concealment of information.

"It is published not enough" means: although new research-results exist these are not published.
The main reason most probably is the intention to keep research activities secret.
The number of these not realized publications can become estimated only roughly .
Subtly differentiated estimations with reference to the research-themes are difficult.

The reflection of research and development activities in the publication processes occurs with atime delay. This delay is caused mainly by the needed times for the manuscript- wri- ting, the editor-work and the print-process.
For journal-articles which are the most frequent publication type the time delay may amount several months.
Due to this delay, the results of publication frequency analyses cannot present a real-time image of ongoing R?D activities, but they reflect the somewhat earlier state of R?D.

This fact has to be taken into consideration when analysing publication frequences and the preceding R?D activities.

With the growing availability and acceptance of the Internet a drastic reducing of the mentioned time delays will get possible. The authors can publish their research results in the Internet in shortest time. Processes for publishing and print and the corresponding waiting periods will be necessary not longer.
The time delays are reduced to the times necessary for writing the publication texts and to insert in the Internet.
However, certain Internet-properties cause its lacking suitability for scientometric analyses of the worldwide publication quantities.
These features are primarily:
 

at first the specific principles of arrangement in the Internet which make it very difficult to  get exact data about the totality of publications that are contained in this network; secondly the missing possibilities for statistical analysing of the publication-quantities which far are scattered in the Internet; thirdly there are no  reliable control-mechanisms for checking the publications when they arrive in the Internet. Through this situation the danger exists that incomplete or scientifically unreliable research results will  published.

The possibility to have access to international database hosts via the Internet does not fundamentally reduce  the delay times. Bottleneck is here not the Internet or more accura- tely the World Wide Web but the unchanged time elapsing  until the storage of a publication in a online database.