The phrase "access to a sample" is correct and usable in written English.
It can be used when discussing the ability to obtain or use a specific example or specimen for analysis, testing, or reference.
Example: "In order to conduct the experiment, we need access to a sample of the new material."
Alternatives: "availability of a sample" or "entry to a sample".
In the case of McAllen, I was able to get help from two private research companies with access to a sample of data from self-insured employers from the two cities.
Access to a sample is possible through the research data centre of the Federal Employment Agency (Dorner et al. 2010).
"By which time their cancers are already very advanced, they've often already spread around the body and often that means that those patients are too ill to go onto a clinical study or for us to get access to a sample of their tumour on which we can then do research.
Gaining access to a sample of migrant nurses proved difficult.
Therefore, we did not have access to a sample of previously-identified fearful patients to use in a group comparison.
The research team had no access to a sample of patients who had not been identified or flagged as having intellectual disabilities.
Population genetic studies generally require two main aspects, (i) the use of polymorphic molecular markers, such as the seven MLST-ISHAM-adopted loci and (ii) access to a sampling size as large as possible.
Shopping areas were chosen because they are safe, accessible public spaces that provide access to a diverse sample of the population.
Fortunately, we have access to a unique sample of leaders in public service: enrollees in a Harvard University executive education program that attracts mid- to high-level government officials and military officers from America and around the world.
In 2015, GSR [Kogan's comapny] did have one-time API access to a random sample of public Tweets from a five-month period from December 2014 to April 2015".
But more recently Willerslev's team, which also led the study of the Anzick child, was given access to a larger sample from a hand bone.
