Medical age assessment
Medical age assessment
The responsible authority in Sweden for assessing the age of an asylum seekers is the Swedish Migration Agency (Migrationsverket). Swedish law states that it is the responsibility of the asylum seeker to make his or her age probable. If the Swedish Migration agency does not assess that an asylum seeker has made his or her age probable, and hence consider to regard the asylum seeker as above the age of eighteen, a medical age assessment is offered. The National Board of Forensic Medicine (Rättsmedicinalverket) conducts this medical age assessment. The result of the assessment is communicated to the Swedish Migration Agency who makes their decision based on the assessment and other evidence presented in the case.
The Swedish Migration Agency have stated that their interest is whether the asylum seeker is more likely younger or older than the age of eighteen. Thus, the National Board of Forensic medicine have chosen methods to correspond to this question. The assessment does not try to determine the actual age of the asylum seeker, only the probability that a person is under or above eighteen years old.
The national board of Forensic Medicine uses two methods for medical age assessment: dental x-ray of the third molar in the lower jaw and MRI of the lower growth plate of the femur bone.
The x-ray images are analysed by two dentists separately. The dentists have no information about the asylum seeker or information about the other dentist’s analysis. The dentist´s only task is to analyse the third molar in the lower jaw and assess whether it has reached the end stage or not.
Only if both dentists (independently of each other) come to the conclusion that the third molar has reached the end stage, this will be the result of the dental analysis. In all other cases the result will be that the third molar has not reached the end stage.
The same procedure is used for the MRI of the knee. Only if both radiologists (independently of each other) come to the conclusion that the lower growth plate of the femur has reached the end stage, this will be the result of the MRI analysis.
A forensic pathologist is then presented with the results of the dental x-ray and MRI. The forensic pathologist has access to the gender and the name of the asylum seeker. To make sure that two cases with the same result (and gender) is assessed the same way, “a decision support system” that suggests an age assessment that corresponds to the result of the analysis is used.
This decision support system is based on a summary of the current scientific data available regarding age assessments using the third molar and MRI of the knee and estimates of the likelihood to be under or above the age of eighteen given the different results of the analysis of the knee and third molar. Since these methods still haven’t been studied in the same population one must be careful when combining the results of the two methods. Therefore the methods have so far been used separately. This means that the likelihood for an asylum seeker to be over eighteen does not increase if both the third molar and the knee have reached the end stage, compared to when only one of the examined body parts has reached the end stage.
The likelihood for a boy between the age of fifteen and eighteen to present a third molar that has reached the end stage is just under 4 percent. For girls this figure is about the same.
Only 50 percent of twenty year olds have reached the end stage of their third molar and the likelihood for an individual (regardless of gender) between the age of eighteen and twenty-one to present a third molar that hasn’t reached the end stage is about 66 percent.
In conclusion, the end stage of the third molar is a good indicator for adulthood, but since so many individuals above the age of eighteen still haven’t reached the end stage, one cannot use the “immature third molar” as an indicator for the asylum seeker to be a minor.
The likelihood for a boy between the age of fifteen and eighteen to present a growth plate that has reached the end stage is just over 6 percent. Since the growth plate of the femur develop earlier in girls, the end stage of the growth plate is not used as an indicator for adulthood in females.
As stated earlier the Swedish model for medical age assessments does not combine the results of the two methods. Nevertheless the Swedish national board of forensic medicine has made statistical estimates regarding the risk for a minor to present end stage/stages in either one or both examined body parts. According to these estimates about 9 percent of boys between the age of fifteen and eighteen will have reached the end stage in either the knee or the third molar. Only 0,4 percent of boys between the age of fifteen and eighteen will have reached the end stage in both the knee and the third molar.
About 50 percent of young men between the age of eighteen and twenty-one will have reached the end stage in either the knee or the third molar and about 28 percent of men between the age of eighteen and twenty-one will have reached the end stage in both the knee and the third molar.
The age assessment reported to the Swedish Migration Agency describes (in words) whether it is more likely that the asylum seeker is younger or older than eighteen. The methods used cannot rule out the possibility that the asylum seeker in spite of the results is under eighteen. The same goes for when the results of the medical age assessments indicate that the asylum seeker is under the age of eighteen.
If a male asylum seeker has reached the end stage in either the knee or the third molar the age assessment given to the Swedish Migration Agency will state that it is more likely that the asylum seeker is eighteen years or older. The margin of error varies with chronological age, but we state that about 10 percent of children close to the age of eighteen might present end stage/stages in at least one of the examined body parts and might therefore be misjudged as adults.
If neither the third molar nor the knee have reached the end stage, the age assessment given to the Swedish Migration Agency will state that it is more likely that the asylum seeker is younger than eighteen. Since about twenty-two percent of young adults between the age of eighteen and twenty-one haven’t reached end stage in either the third molar or the knee – the risk is about twice as big for young adults to be misjudged as children compared to the risk for children to be misjudged as adults.
For females the assessment is somewhat different due to the fact that the end stage of the knee can’t be used as an indicator of adulthood. The decision support system is therefore designed to recommend different age assessments with regards to gender.