The National Health Survey Act of 1956 provides for the establishment and continuation of a National Health Survey to obtain information about the health status of the population in the United States. The psychological component of the Survey is included to provide a more complete assessment of the health and well-being of the population. A first effort in developing specific psychological examination procedures within an overall plan of psychological assessments was directed toward developing a test that could be used in assessing level of development in verbal ability. The result was the Basic Word Vocabulary Test, which was developed to provide a measurement instrument of word knowledge acquisition with two additional properties that are not extant in any other standardized vocabulary test (1) a carefully specified population of words with (2) a range of application from about the third level of literacy to the highest level of word knowledge acquisition. These two properties permit assessment of a wide range of vocabulary development in terms of absolute level and relative standing in reference to various normative groups on one continuous scale. The results of the studies to date and copies of the tests are included. (TO)