Mayo's Older Americans Normative Studies: Age- and IQ-Adjusted Norms for the Wechsler Memory Scale--Revised

ABSTRACT

Normative data sets for standardized neuropsychometric instruments often include adjustments for subject variables. There are reasons to believe, however, that improvements in interpretive accuracy that result from such adjustments are less than optimal. In particular, “years of formal education” may be less closely related to test performances than is general intellectual functioning. In this third of four reanalyses of results from the Mayo Clinic's Older Americans Normative Studies (MOANS) databases, age-adjusted index and scaled scores for the Wechsler Memory Scale-Revised were found to be more strongly associated with Mayo age-adjusted WAIS-R Full Scale IQ scores (rs = .271 to .631) than with education (rs = .089 to .310) for healthy older examinees between 56 and 99 years of age. These associations were strongest for Attention/Concentration and General Memory Index scores and, in general, for individuals with average intelligence (cf. Dodrill, 1997 1999). Tables of age- and IQ-adjusted percentile equivalents of Mayo age-adjusted WMS-R index scores and MOANS age-adjusted WMS-R subtest scaled scores are presented for eleven age ranges and seven IQ ranges.

Notes

^a The reader is advised that these age ranges do not coincide with the age ranges or cell sizes that appear in the normative data tables that appear below.

^b “Non-Caucasian” includes African American, Latino, Canadian, and Western European.

Note. Scaled scores and IQ scores are age-adjusted. MOANS = Mayo's Older Americans Normative Studies; WMS-R = Wechsler Memory Scale—Revised; FSIQ = Full Scale IQ; VIQ = Verbal IQ; PIQ = Performance IQ.

¹Participants' Verbal Memory Index, Attention/Concentration Index, Mental Control, Digit Span, Logical Memory (I, II, and Retention), and Verbal Paired Associates II scores were more strongly associated with their VIQ scores than with their PIQ scores (data not reported here). In contrast, their Nonverbal Memory Index, General Memory Index, Delayed Recall Index, Percent Retention Index, Visual Memory Span, Verbal Paired Associates I, Figural Memory, Visual Reproduction (I, II, and Retention), and Visual Paired Associates scores were more strongly associated with their PIQ scores than with their VIQ scores. These differences are largely consistent with the broad—and imperfect—characterization of Verbal and Performance subtests as involving language-based functions and visually-based problem-solving abilities, respectively. In most cases (11 of 20 index and scaled scores), however, test scores were more strongly associated with FSIQ than with either VIQ or PIQ. For this reason, and to ensure that the norms that are reported herein are comparable to those from other manuscripts in this series, we chose to use FSIQ as the stratification factor for WMS-R data.

Note. MOANS = Mayo's Older Americans Normative Studies; WMS-R = Wechsler Memory Scale—Revised; FSIQ = Full Scale IQ; VIQ = Verbal IQ; PIQ = Performance IQ.

^a p < .05.

^b p < .01.

²Although non-zero correlations were found between age and all six WMS-R index scores, these scores were calculated from age-adjusted scaled scores. We were therefore unable to carry out supplementary raw-data correlational analyses for these summary indices.

³The exceptions to this trend were clearly stronger correlations for each test at the lowest (<95) and highest (>119) IQ score ranges. This probably reflects the fact that these class intervals included many more potential IQ score values than did the remaining five-point intervals.

Note. MOANS = Mayo's Older Americans Normative Studies; WMS-R = Wechsler Memory Scale—Revised; FSIQ = Full Scale IQ.

^a To use, locate desired index score and FSIQ column and find percentile equivalent of MOANS scaled score sum or age-adjusted Mayo Index Score (cf. TCN, 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ column, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN, 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ column, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN, 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ column, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN, 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ column, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN, 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ column, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN, 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ colunm, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN. 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ colunm, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN. 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ colunm, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN. 6, 49–82).

^a To us, find table that corresponds to examinee's age, locate appropriate test score and FSIQ column, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN, 6, 49–82).

^a To use, find table that corresponds to examinee's age, locate appropriate test score and FSIQ column, and determine percentile equivalent of raw score or age-adjusted MOANS scaled score (cf. TCN, 6, 49–82).