tests include the "numbers connecting test" A and B (measuring the speed at which one could connect randomly dispersed numbers 1–20), the "block design test" and the "digit-symbol test". In 2009 an expert panel concluded that neuropsychological test batteries aimed at measuring multiple domains of cognitive function are generally more reliable than single tests, and tend to be more strongly correlated with functional status. Both the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and PSE-Syndrom-Test may be used for this purpose. The PSE-Syndrom-Test, developed in Germany and validated in several other European countries, incorporates older assessment tools such as the number connection test. Treatment Those with severe encephalopathy (stages 3 and 4) are at risk of obstructing their airway due to decreased protective reflexes such as the gag reflex. This can lead to respiratory arrest. Transferring the person to a higher level of nursing care, such as an intensive care unit, is required, and intubation of the airway is often necessary to prevent life-threatening complications (e.g., aspiration or respiratory failure). Placement of a nasogastric tube permits the safe administration of nutrients and medication. The treatment of hepatic encephalopathy depends on the suspected underlying cause (types A, B, or C) and the presence or absence of underlying causes. If encephalopathy develops in acute liver failure (type A), even in a mild form (grade 1–2), it indicates that a liver transplant may be required, and transfer to a specialist centre is advised. Hepatic encephalopathy type B may arise in those who have undergone a TIPS procedure; in most cases this resolves spontaneously or with the medical treatments discussed below, but in a small proportion of about 5%, occlusion of the shunt is required to address the symptoms. In hepatic encephalopathy type C, the identification and treatment of alternative or underlying causes is central to the initial management. Given the frequency of infection as the underlying cause, antibiotics are often administered empirically (without knowledge of the exact source and nature of the infection). Once an episode of encephalopathy has been effectively treated, a decision may need to be made on whether to prepare for a liver transplant. Diet In the past, it was thought that consumption of protein even at normal levels increased the risk of hepatic encephalopathy. This has been shown to be incorrect. Furthermore, many people with chronic liver disease are malnourished and require adequate protein to maintain a