Systematic evidence is more difficult to find.There are certainly signs that home-schoolers are thriving.
Some of the more complex, older cases - where evidence is more difficult to gather - tend to end up with the financial ombudsman service.
By definition, therefore, clinical evidence is more difficult to build in rare than in frequent cancers.
Given the challenges of tracking effects over multiple human lifespans, the evidence is more difficult to interpret, particularly with respect to potential mechanisms, says Tessa Roseboom, a professor of early development and health at the Academic Medical Center in Amsterdam, the Netherlands.
Along with the limited number of studies targeting the elderly population, the low quality of the existing studies makes the interpretation of the evidence still more difficult; for example, only one third of the studies included in this review were of high quality.
In some circumstances, cases can be opened or reopened after the statute of limitations has expired, if new evidence appears; but finding new evidence will grow more difficult with time as well.
On the night of the shooting, as officer after officer arrived at the scene, ducked under the yellow tape and approached Sergeant Drenth's body and his patrol car parked nearby, the already confused evidence became even more difficult to interpret, the police said.
The aggregation problems work against the goal of updating the evidence, making it more difficult to draw inferences beyond 2004 for the wage and employment analysis and 2003 for the family income analysis, although we also report the estimates extending as far as we can.
For a field such as palliative care, issues around evidence are made more difficult by the multidisciplinary and multispecialty nature of the clinical care.
One is the body of scientific evidence, which is becoming more difficult for Mr Bush to refute.
