By Nicolas Jonas
Analyst, OECD Directorate for Education and Skills
The Survey of Adult Skills, part of the OECD’s Programme for International Assessment of Adult Competencies (PIAAC), is a key source of information on adults’ proficiency in the information-processing skills that are essential for full participation in modern societies – including numeracy skills. PIAAC data reveal large disparities in numeracy proficiency not only across countries, but between different adult subgroups within countries, as well. Poor numeracy has detrimental effects in many aspects of life, as adults must be able to use numeracy skills in many professional and everyday situations – for example when making decisions, dealing with numerical information, or trying to assess the relevance of figures.
A new OECD working paper analyses data from the Survey of Adult Skills to identify the links between adult proficiency in numeracy and the intensity of numeracy use in everyday and work-related situations. The paper shows that in most countries, engaging intensively in numeracy practices is crucial for improving or maintaining skills after leaving education. In addition, proficiency and engagement in practices are both positively associated with a wide range of dimensions of individual well-being, such as reported health.
The correlation between health and numeracy skills is strong in most countries and economies that participated in the Survey of Adult Skills. On average, the probability of reporting good to excellent health is 22 percentage points higher for adults at Level 4 or 5 for numeracy than for adults at Level 1 or below. The gap is much greater among older adults: among 16- to 25-year-olds, the difference in health is 5.5 percentage points, whereas among people aged 55 to 65, the difference is 32 percentage points. The data do not indicate to what extent this discrepancy across age groups is due to a generational effect, rather than an effect of ageing.
When the intensity of everyday engagement in numeracy activities is added to this analysis, it becomes clear that intensity plays a significant role in the probability of reporting poor or very poor health – as significant as an individual’s level of numeracy. It suggests that people with very strong skills in numeracy, and those who make frequent use of numeracy in a wide range of situations, benefit from a considerable comparative health advantage over other adults, all things being equal.
The main reason could be that in today’s healthcare systems, the burden of decision making is increasingly transferred to patients, who must therefore understand numerical information about their own health and effectively manage their care. Greater proficiency in numeracy and habitual use of numeracy skills are thus associated with greater effectiveness in personal health management, greater effectiveness in medical decision making and better understanding of quantitative medical indicators, such as the risks and effects of treatment.