between the two competing hypotheses was the fact that while the link between Hepatitis B and a higher likelihood of male birth had been documented, there was little information available on the strength of this link and how it varied by which of the parents were the carriers. Furthermore, most prior medical studies did not use a sufficiently high number of observations to convincingly estimate the magnitude of the relationship. However, in a 2008 study published in the American Economic Review, Lin and Luoh utilized data on almost 3 million births in Taiwan over a long period of time and found that the effect of maternal Hepatitis B infection on the probability of male birth was very small, about one quarter of one percent. This meant that the rates of Hepatitis B infection among mothers could not account for the vast majority of missing women. The remaining possibility was that it was the infection among fathers that could lead to a skewed birth ratio. However, Oster, together with Chen, Yu and Lin, in a follow up study to Lin and Luoh examined a data set of 67,000 births (15% of whom were Hepatitis B carriers) and found no effect of infection on birth ratio for either the mothers or fathers. As a result, Oster retracted her earlier hypothesis. Other diseases In a 2008 study, Anderson and Ray claim that other diseases may explain the "excess female mortality" across Asia and sub-Saharan Africa. By comparing relative death rates of females to males in developed countries to the country in question, Anderson and Ray find that 37 to 45% of the missing women in mainland China can be traced to pre-birth and infancy stage termination factors, whereas only around 11% of India's missing women were caused by similar factors, pointing to the fact that the loss is spread across different ages. They find that by and large, the main cause for female deaths in India is cardiovascular disease. "Injuries" is the number two cause of female deaths in India. Both of these causes are far greater than maternal mortality and abortion of fetuses, though "Injuries" may be directly related to gender discrimination. Their findings for mainland China also attribute missing women of older ages to cardiovascular and other non-communicable diseases, accounting for a large portion of excess female deaths. However, the largest bracket of missing women is in the 0-4 age group,