SPMS was defined for this study as progressive deterioration observed and sustained for at least 6 months with or without superimposed attacks. Percentage of subjects converting to SPMS were stratified by actual treatment group and baseline EDSS. Baseline EDSS defined as lowest of the EDSS scores obtained during BENEFIT screening or baseline (less than or equal to [<=] median or greater than [>] median).

SPMS was defined for this study as progressive deterioration observed and sustained for at least 6 months with or without superimposed attacks. Time to SPMS was represented by Kaplan-Meier estimates.

The EDSS scale is a method of quantifying disability in multiple sclerosis in eight functional systems and values vary between 0="normal neurological examination" and 10="death due to MS" measured in half-points on a scale. The first levels 1.0 to 4.5 refer to people with a high degree of ambulatory ability and the subsequent levels 5.0 to 9.5 refer to the loss of ambulatory ability. The range of main categories include (0) = normal neurologic exam; to (5) = ambulatory without aid or rest for 200 meters; disability severe enough to impair full daily activities; to (10) = death due to MS.

The EDSS scale is a method of quantifying disability in multiple sclerosis in eight functional systems and values vary between 0="normal neurological examination" and 10="death due to MS" measured in half-points on a scale. EDSS progression was defined as an increase in the EDSS of at least 1.0 point compared to initial EDSS score or an increase in the EDSS of at least 1.5 points compared to initial EDSS score, if this score was = 0 points. Confirmed EDSS progression status in any of the previous BENEFIT studies (304747, 305207, 311129) was defined as an EDSS progression observed at two consecutive scheduled visits at least 140 days apart from each other. A confirmed EDSS progression is defined as a confirmed EDSS progression in any of the previous BENEFIT studies or EDSS progression in BENEFIT 11. A sustained EDSS progression is defined as a confirmed EDSS progression in any of the previous BENEFIT studies sustained up to and including the BENEFIT 11 visit.

The EDSS scale is a method of quantifying disability in multiple sclerosis in eight functional systems and values vary between 0="normal neurological examination" and 10="death due to MS" measured in half-points on a scale. EDSS progression was defined as an increase in the EDSS of at least 2.5 points compared to initial EDSS score, if this score was <= 3.5 points, or an increase in the EDSS of at least 2.0 points compared to initial EDSS score, if this score was > 3.5 points. Confirmed EDSS increase status in any of the previous BENEFIT studies (304747, 305207, 311129) was defined as an EDSS increase confirmed at scheduled visits after at least 140 days. A confirmed EDSS increase is defined as a confirmed EDSS increase in any of the previous BENEFIT studies or EDSS increase in BENEFIT 11.

The DSS 3, and DSS 6 are important milestones in the course of disability progression and were documented if reached by the subject.

The DSS 3 is an important milestones in the course of disability progression and were documented if reached by the subject. The time point of reaching DSS 3 was obtained retrospectively in the BENEFIT 11 study. Time to respective DSS is the difference between the date of respective DSS and the date of the BENEFIT baseline visit +1. Subjects without event at BENEFIT 11 were censored at the BENEFIT 11 visit. This constituted a right-censored observation. Cumulative probability of reaching DSS 3 at Year 11 were estimated by Kaplan-Meier.

The DSS 6 is an important milestones in the course of disability progression and were documented if reached by the subject. The time point of reaching DSS 6 was obtained retrospectively in the BENEFIT 11 study. Time to respective DSS is the difference between the date of respective DSS and the date of the BENEFIT baseline visit +1. Subjects without event at BENEFIT 11 were censored at the BENEFIT 11 visit. This constituted a right-censored observation. Cumulative probability of reaching DSS 6 at Year 11 were estimated by Kaplan-Meier.

The MSFC score consists of three subtests (Timed 25 Foot Walk, 9 Hole Peg Test, 3" Paced Auditory Serial Addition Test [PASAT]) whose Z-standardized results (based on baseline values on Day 1 in Study 304747) were combined into a composite score including upper and lower extremities function, and cognitive function. Standardized results (Z-scores) of the subtests and the overall MSFC Z-score as an average of the three Z-scores were derived using baseline data pooled over both treatment arms as reference population. Higher Z-scores reflect a better neurological status.

The MSSS added the element of disease duration to the EDSS and was designed to provide a measure of disease severity. It was derived from the EDSS during the data evaluation. The MSSS corrects the EDSS for the duration of disease by using an arithmetical method to compare an individual's disability with the distribution of scores in case of having equivalent disease duration.

The Paced Auditory Serial Addition Test (PASAT) is a measure of cognitive function that specifically assesses auditory information processing speed and flexibility, as well as calculation ability.

The Symbol Digit Modalities Test (SDMT) is a cognitive test for sustained attention, concentration, and information-processing speed, with a high sensitivity. Nine different geometrical symbols have one corresponding number each. One-hundred-ten symbols are presented without these numbers; the subject must find the matching number from the top line and verbalize the number to the examiner. The subject is allowed to proceed for 90 seconds, and the number of correct responses in 90 seconds is counted as the total correct score. Also, the numbers of correct responses at 30 and 60 seconds were recorded in this study. Total score ranged from 0 (worst outcome) to best (outcome).

A relapse was defined as the appearance of a new neurological abnormality or the reappearance of a neurological abnormality, separated by at least 30 days from onset of a preceding clinical demyelinating event. The time to the onset of recurrent relapses was determined for each subject according to the counting process representation for recurrent events. Time to a relapse was right censored if a relapse risk period ended without relapse. Based on the Andersen Gill model the hazard ratio for recurrent relapses was estimated with actual treatment in BENEFIT (304747; i.e. IFNB-1b 250 microgram vs. placebo), steroid use during first event (yes vs. no), onset of disease (multifocal vs. monofocal) and number of T2 lesions on BENEFIT screening MRI (categorized as 2-4, 5-8, >=9) included in the model.

The annualized relapse rate is defined as total number of relapses up to Year 11 divided by the total observation time (last clinical visit minus first day of study treatment administration plus 1 of all subjects) in years.

Date of use of ambulatory device is defined as the retrospectively obtained time point of first use/dependence. Time to use of ambulatory device is the difference between the date of first use/dependence and the date of the BENEFIT baseline visit +1.

Date of dependence from ambulatory device is defined as the retrospectively obtained time point of first use/dependence. Time to dependence from ambulatory device is the difference between the date of first use/dependence and the date of the BENEFIT baseline visit +1. Cumulative probability of dependence of ambulatory device for walking represented by Kaplan-Meier estimates at Year 11.

Subject's employment status was categorized as 'retired', 'homemaker', 'long term disability', 'employment less than 20 hours (hrs) per week (hrs/week)', employment more than 20 hours per week, 'early retired', 'other', and 'missing'.

Subject's MS impact on employment was categorized as, 'unrelated to MS condition', 'ceased work due to MS', 'never worked', 'reduced working hours', or missing.

Hospitalizations were assessed at year 11 only referring to past 12 months. Number of hospitalizations per subject were categorized as, 'none', '1', '2', '3', and '6'.

Visits to Other Specialists were assessed at year 11 only referring to past 12 months. The visits to other specialists were categorized as, 'missing', 'no', 'yes', 'never', and 'unsure'. The other specialists includes, neurologist, nurse clinician, home health aide, visiting nurse, physiotherapist, psychiatrist, psychologist, physician, urologist, social worker and gynecologist.

Resources use data was assessed cross-sectionally at 11 years. Supportive care was assessed as "assistance given" for the help from family members or friends with "care given" for the number f hors per week needed, as well as "ambulatory services-yes/no" with sub-categories home care, home help, day care center, meals on wheels and child care for the help from professional caregiver.

Resources use data was assessed cross-sectionally at 11 years. Additional ambulatory services during relapse were categorized as, 'missing', 'no', and 'yes'. The additional ambulatory services during relapses were home care, home help, day care center, meals on wheels, and child care.

Resources use data was assessed cross-sectionally at 11 years. The kind of adaptation was categorized as "other part of living", "star lift". "ramps", "alarm", "work", "car", "walking aids", "wheel chair", "spectacles", "special kitchen utensils", "special hygiene utensils", "special writing devices" and " other" with subcategories as 'missing', 'no', and 'yes'.

The CES-D is a measure of depressive symptomatology. The CES-D was a self-administered questionnaire for adults comprising 20 items which evaluated the frequency and severity of depressive symptoms. Subjects were asked to recall the previous 7 days. The total score (0-60) was the sum of the scores of the 20 items. A score of >= 16 suggested a mild to moderate level of depressive symptoms; a score >21 suggested major depressive symptoms.

The cognitive and physical fatigue was assessed by the FSMC. The scale comprised of 20 questions (10 items for physical and 10 items for cognitive fatigue) and could be completed within 5 minutes. The items are rated on a 5-point Likert scale (1=does not apply at all to 5=applies completely). The FSMC total score ranges from 20 to 100 where a higher score is associated with a higher severity of fatigue.

The Functional Assessment of Multiple Sclerosis (FAMS) instrument is a self-reporting, multi-dimensional, health-related QoL index for use in subjects diagnosed with MS. It comprised 58 items on 7 subscales (mobility, symptoms, emotional well-being, general contentment, thinking and fatigue, family/social wellbeing, and additional concerns). FAMS-TOI is the sum of the subscale scores mobility, symptoms, thinking/fatigue, and additional concerns. The items were rated on a 5-point scale (0 to 4). Score range of FAM-TOI is 0 to 148; the higher the score, the higher the quality of life. The evaluation period was the previous 7 days.

The Functional Assessment of Multiple Sclerosis (FAMS) instrument is a self-reporting, multi-dimensional, health-related QoL index for use in subjects diagnosed with MS. It comprised 58 items on 7 subscales: mobility, symptoms, emotional well-being, general contentment, thinking and fatigue, family/social wellbeing, and additional concerns. The items were rated on a 5-point scale (0 to 4). Total score is sum of all sub-scale scores except 14 items for "Additional concerns", ranging 0 to 176; the higher the score, the higher the quality of life. The evaluation period was the previous 7 days.

The EQ-5D measured five state-of-health dimensions: mobility, self-care, usual activities (work, leisure, etc.), pain/discomfort, and anxiety/depression. Every item had a score of 1 (no problems), 2 (some/moderate problems), or 3 (extreme problems). An individual's health status was defined in a combination of 5 digits. Subjects with missing answers to all questions were not considered for the respective visit.

Based on large population surveys, an algorithm was developed to combine the recordings of each of these five EQ-5D dimensions in 1 single HRQoL score, ranging from +1 (best imaginable HRQoL score) to -0.59 (worst imaginable HRQoL score). A relatively higher score represents better quality of life.

Subjects were treated exclusively at the discretion of their treating physician and according to locally applicable standards and treatment guidelines. Subjects received second line therapy as a MS treatment such as alemtuzumab, cyclophosphamide, ciclosporin, fingolimod, methotrexate, mycophenolate mitoxantrone, natalizumab, etc.

Subjects were treated exclusively at the discretion of their treating physician and according to locally applicable standards and treatment guidelines. All DMTs other than interferon beta, interferon beta-1a and interferon beta-1b were recorded as DMT other than IFNB.

Contrast-enhanced MRI (with an extracellular gadolinium-based contrast agent) technique was used for the evaluation of brain lesions in MS. Newly active lesions defined as displaying either new enhancement on T1-weighted scans, or non-enhancing on T1-weighted scan but new on T2-weighted scans.

Contrast-enhanced MRI (with an extracellular gadolinium-based contrast agent) technique was used for the evaluation of brain lesions in MS. Number of lesions on T1- and T2-Weighted scans were recorded.

Contrast-enhanced MRI (with an extracellular gadolinium-based contrast agent) technique was used for the evaluation of brain lesions in MS. Volume of lesions on T1- and T2-Weighted scans were recorded.

Contrast-enhanced MRI (with an extracellular gadolinium-based contrast agent) technique was used for the evaluation of brain lesions in MS. Brain volume was analysed and reported.

OCT is a noninvasive ocular imaging recognized in MS as a marker of axonal loss. Retinal nerve fiber layer (RNFL) thinning measured by OCT in subjects with MS occurs even in the absence of acute optic neuritis and is associated with worse scores for low-contrast letter acuity and other visual acuity tests. OCT measures peripapillary RNFL.

OCT is a noninvasive ocular imaging recognized in MS as a marker of axonal loss. OCT is a potential method for capturing neuronal in addition to axonal degeneration in MS.

OCT is a noninvasive ocular imaging recognized in MS as a marker of axonal loss. OCT is a potential method for capturing neuronal in addition to axonal degeneration in MS.

OCT is a noninvasive ocular imaging recognized in MS as a marker of axonal loss. OCT is a potential method for capturing neuronal in addition to axonal degeneration in MS.

Standard clinical ophthalmic examination and test were applied for visual assessment and the differential diagnosis of OCT-related findings.

Standard clinical ophthalmic examination and test were applied for visual assessment and the differential diagnosis of OCT-related findings. Ocular medical and surgical history, visual acuity (Early Treatment Diabetic Retinopathy Study Chart), low-contrast letter acuity (Sloan charts), and eye examination through slit-lamp biomicroscopy were assessed.

Standard clinical ophthalmic examination and test were applied for visual assessment and the differential diagnosis of OCT-related findings. Ocular medical and surgical history, visual acuity (Early Treatment Diabetic Retinopathy Study Chart), low-contrast letter acuity (Sloan charts), and eye examination through slit-lamp biomicroscopy were assessed.

Number of subjects with intake of Vitamin D were categorized as, 'since beginning of the BENEFIT study', and 'within the past 12 months'.