In 1981, the socialist countries of the world enjoyed higher living standards than capitalist countries in 28 out of 30 cases. This is the conclusion of a 1986 study called Economic Development, Political-Economic System, and the Physical Quality of Life [ncbi]. I was quite surprised to learn this given the fact that socialist countries have quite a bad reputation. Comparing data from the world bank and UNICEF about the world's nations, it turns out that in almost all cases, inhabitants of a capitalist country were worse off. Socialist countries had a healthier population with higher expected lifetime, higher literacy rates, lower infant mortality and a higher daily calorie count (with healthier food). That is on top of the very obvious lack of unembloyment and abject poverty a state-run economy provides.
The only way to make capitalist countries come out on top is by making bad comparisons. Highly developed capitalist countries like the US and Britain obviously have the edge over the poorer and less developed regions of the world. That does not, however, show that capitalism is superior to socialism. When you compare socialist and capitalist countries adjusted by level of economic development -- like the study does -- socialist countries take the crown in 28 out of 30 cases.
"The relationships between PQL and political-economic system deserve more serious attention than they have received in the past. Our findings indicate that countries with socialist political-economic systems can make great strides toward meeting basic human needs, even without extensive economic resources. When much of the world's population suffers from disease, early death, malnutrition, and illiteracy, these observations take on a meaning that goes beyond cold statistics." [ibid]