Statement of Principles concerning giant cell arteritis (Reasonable Hypothesis) (No. 11 of 2021)

This instrument is a Statement of Principles (SoP) made under subsection 196B(2) of the Veterans’ Entitlements Act 1986 (VEA). It specifies the minimum factors that must exist before it can be said that a reasonable hypothesis has been raised connecting giant cell arteritis (GCA), or death from GCA, with the circumstances of a person’s relevant service as defined in VEA and the Military Rehabilitation and Compensation Act 2004 (MRCA). The instrument does not create a right to compensation or a duty on any person; rather, it operates as a binding evidentiary standard for decision makers. When a veteran, peacekeeper, or member of the forces makes a claim under VEA section 120A or MRCA section 338, the decision maker must apply this SoP to determine whether the claimed condition is related to service. The SoP sets out three alternative factors: smoking at least 10 pack years before the clinical onset of GCA, smoking at least 10 pack years before the clinical worsening of GCA, or inability to obtain appropriate clinical management for GCA. If at least one factor exists and is related to the person’s relevant service, a reasonable hypothesis is deemed to exist, shifting the evidentiary burden. The instrument is a legislative instrument subject to disallowance by Parliament, and it replaces any previous SoP on GCA. It applies only to claims where the standard of proof is the “reasonable hypothesis” test, which is the lower of the two standards under the VEA. The other standard, “reasonable satisfaction,” is covered by a separate SoP for the same condition. The instrument includes detailed definitions of giant cell arteritis, terminal events, pack year, and relevant service, and it cross refers to other SoPs when a factor in section 9 involves another injury or disease that has its own SoP. Importantly, the SoP does not itself award compensation or establish liability; it merely prescribes the medical scientific evidence threshold that must be met for a claim to proceed. The practical effect is to reduce discretion in claims assessment by requiring adherence to a fixed set of criteria, which accelerates some claims but may also exclude claims that do not fit the prescribed factors even where there is plausible causation.

The central concept in this SoP is the reasonable hypothesis standard. Under VEA section 120A, a hypothesis connecting an injury, disease, or death with service is reasonable if it is a hypothesis pointed to by the facts and supported by sound medical scientific evidence. This SoP is the Repatriation Medical Authority’s declaration of what factors constitute that sound evidence for GCA. The instrument therefore embodies the RMA’s view that GCA can be related to relevant service only through three specific pathways.

Giant cell arteritis is defined in section 7(2) as a systemic autoimmune vasculitis that involves large and medium sized arteries and principally affects the cranial branches of the carotid arteries. The definition is narrower than some clinical descriptions; it excludes vasculitis affecting only the aorta without cranial involvement. The ICD 10 AM codes M31.5 and M31.6 are used for statistical purposes but the definition in subsection (2) controls.

Pack year is defined in the Schedule 1 Dictionary as the amount of tobacco consumed in smoking 20 cigarettes per day for one year, or an equivalent amount of tobacco products. The amended definition from 2022 provides a weight based equivalence: 7,300 grams of smoking tobacco by weight, whether in cigarettes, pipe tobacco, or cigars. This is important because it removes ambiguity about how to calculate pack years for mixed tobacco use. The note explains the formula: number of cigarettes per day divided by 20, multiplied by years smoked.

Clinical onset and clinical worsening are not defined in the instrument but are standard terms in Statements of Principles. Clinical onset refers to the first manifestation of symptoms that would lead a medical practitioner to diagnose GCA. Clinical worsening refers to a significant increase in severity or complications after diagnosis. The instrument imposes a temporal limit for smoking cases: the onset or worsening must occur within 20 years of cessation. If smoking continues, no such limit applies.

Inability to obtain appropriate clinical management is a factor that applies only to material contribution or aggravation (section 10(2)). It is a broad factor that could cover any reasonable medical treatment that was unavailable due to service related reasons, such as absence of a specialist, denial of treatment, or service related constraints. The instrument does not define “appropriate clinical management,” leaving it to medical judgment.

The primary persons affected are veterans, members of Peacekeeping Forces, and members of the Forces under VEA, as well as members covered by MRCA, who have or have had giant cell arteritis and are claiming compensation for that condition or for death from GCA. These individuals must demonstrate that at least one of the three factors in section 9 exists and is related to their relevant service. The SoP directly determines the success or failure of their claims. Secondarily, it affects their dependants and legal representatives, who must gather evidence of smoking history or inability to obtain appropriate clinical management.

Decision makers within the Department of Veterans’ Affairs (DVA), the Veterans’ Review Board, the Administrative Appeals Tribunal, and the courts are bound to apply this SoP when assessing claims under VEA section 120A and MRCA section 338. They cannot accept a reasonable hypothesis that relies on factors outside the SoP, unless the SoP itself is later amended or overturned. This restricts their discretion and standardises outcomes.

Medical practitioners providing reports for claimants are affected because they must address the specific factors: they must calculate pack years and confirm whether clinical onset occurred within 20 years of cessation, or opine on inability to obtain appropriate clinical management. The SoP may influence clinical documentation practices and the types of evidence gathered.

The Repatriation Medical Authority itself is indirectly affected as the maker of the instrument. It must keep the SoP under review and update it as medical scientific evidence changes. The 2022 amendment to the pack year definition shows the Authority’s responsiveness to definitional issues.

Taxpayers and the compensation system are affected because the SoP determines which claims are accepted and therefore which compensation payments are made. By narrowing the acceptable causal pathways to three factors, the instrument may reduce the number of successful claims compared to a more open ended test, potentially lowering total compensation costs. However, it may also increase litigation over the interpretation of factors, especially the “inability to obtain appropriate clinical management” factor, which is less objective than the smoking factor.

Legal professionals advising claimants must understand the SoP’s structure, the definitions, and the interaction with other SoPs (section 11). They must ensure that evidence is tailored to the instrument’s requirements, and they may need to challenge the instrument itself if they believe the RMA failed to consider relevant medical evidence. The SoP also affects experts who provide medico legal opinions.

The SoP does not impose direct duties on any person, but it creates a framework of rights and obligations within the claims process. The key right is that a claimant whose circumstances satisfy at least one factor in section 9, and whose factor is related to relevant service, is entitled to have their claim assessed on the basis that a reasonable hypothesis has been raised. This means the decision maker must accept the connection unless there is evidence to the contrary that proves the hypothesis is unreasonable (the standard under VEA section 120A). In practice, satisfying the SoP factors shifts the burden to the decision maker.

The RMA has a duty under VEA section 196B(2) to determine Statements of Principles based on sound medical scientific evidence. This SoP reflects that duty. Once made, the RMA has no ongoing duty under this instrument, but it may amend it as new evidence emerges. The Authority also has a duty to ensure the instrument is consistent with the VEA and not ultra vires.

Decision makers have a duty to apply the SoP correctly. If a factor is present but the decision maker finds that the hypothesis is still not reasonable (for example, because the smoking history does not meet the 10 pack year threshold or the temporal limit), they must provide reasons. The decision maker also has a duty to ensure that the factor is related to service as required by section 10(1). For factors 9(2) and 9(3), which apply only to material contribution or aggravation of a GCA that existed before or during (but did not arise out of) service, the decision maker must verify this temporal relationship.

Claimants have the right to provide evidence of any of the three factors. They also have the right to rely on section 11, which incorporates by reference the factors of any other SoP that covers an injury or disease mentioned in a factor of this SoP. For example, if a factor refers to “hypertension” and there is a separate SoP for hypertension, the factors of that SoP also apply. This prevents fragmentation and ensures consistency.

The instrument does not create a right to retrospective application. It applies to claims made on or after the date of commencement (25 January 2021) and to claims under VEA section 120A or MRCA section 338 regardless of when the service was rendered. There is no duty on the claimant to prove that the factor is the only possible connection; the SoP merely sets a minimum.

This SoP itself does not contain penalty provisions. Penalties for non compliance arise from the broader legislative framework. If a claimant provides false or misleading information to satisfy a factor, they may be prosecuted under the Criminal Code or under VEA section 56C (false statements), which carries penalties of imprisonment up to 12 months. Similarly, if a medical practitioner knowingly provides a false report regarding pack years or clinical management inability, they may be liable for fraud.

Enforcement of the SoP occurs through the claims and review process. If a decision maker fails to apply the SoP correctly, the claimant can seek review by the Veterans’ Review Board, the Administrative Appeals Tribunal, or the Federal Court. The Court can set aside the decision and remit it for reconsideration. There is no dedicated enforcement body; rather, the instrument is enforced through administrative law remedies.

The practical “penalty” for a decision maker who misapplies the SoP is that their decision is likely to be set aside on review, causing delay and costs. For the system as a whole, a pattern of misapplication could lead to additional training requirements or amendments to the instrument.

The instrument is subject to disallowance by either House of Parliament within 15 sitting days after tabling. If disallowed, it ceases to have effect, and the previous SoP (if any) would revive. This is a political enforcement mechanism that ensures the RMA does not exceed its authority.

For claimants, the most significant consequence is claim rejection. If they fail to satisfy one of the three factors, they cannot succeed under the reasonable hypothesis standard. They may still succeed under the higher “reasonable satisfaction” standard if that SoP applies, but that threshold is more demanding. The instrument therefore operates as a gatekeeper, and the penalty for non compliance is exclusion from the lower standard.

This SoP is made under VEA section 196B(2) and must be read in conjunction with VEA section 120A, which directs that a reasonable hypothesis is deemed to be raised if the material points to a hypothesis that is supported by sound medical scientific evidence and that is consistent with the SoP. The SoP is the authoritative statement of what constitutes sound medical scientific evidence for GCA. It overrides any general medical opinion to the contrary, though a decision maker can still find that the hypothesis is unreasonable if other evidence outweighs the SoP factors.

The instrument also interacts with MRCA section 338, which applies the same reasonable hypothesis test for members covered by that Act. The definition of “relevant service” in the Dictionary includes both VEA and MRCA categories, ensuring that the SoP applies uniformly across both compensation schemes. This avoids inconsistent outcomes for veterans and defence members with similar conditions.

Section 11 of the SoP incorporates other Statements of Principles by reference. If a factor in section 9 (such as inability to obtain appropriate clinical management for GCA) involves another injury or disease that has its own SoP, the factors of that other SoP apply. This creates a network of linked instruments. For example, if the inability to obtain appropriate clinical management is due to a mental health condition, the SoP for that mental health condition would need to be considered. This cross referencing prevents the SoP from becoming a closed system.

The ICD 10 AM coding references (M31.5, M31.6) are used for administrative purposes, but the definition of GCA in the SoP is autonomous. This avoids conflict with changing ICD editions. If the ICD code changes, the SoP remains valid because its definition does not depend on the code.

The instrument interacts with the Acts Interpretation Act 1901 and the Legislation Act 2003 as a legislative instrument. It must be registered on the Federal Register of Legislation, is subject to disallowance, and must be complied with by rule makers. The amendment to the pack year definition was made under the Legislation Act 2003.

Finally, the SoP does not affect other compensation laws such as the Safety, Rehabilitation and Compensation Act 1988 (for Commonwealth employees) or state workers compensation schemes, because those schemes have their own causation rules. However, a person may have claims under both VEA and other laws; this SoP applies only to VEA/MRCA claims.

The original instrument, “Statement of Principles concerning giant cell arteritis (Reasonable Hypothesis) (No. 11 of 2021)”, was registered on 4 January 2021 and commenced on 25 January 2021. It replaced any previous SoP on GCA. The original text is not provided in the compilation, but the compilation includes amendments up to 19 September 2022.

The only amendment to date is the “Veterans’ Entitlements (Statements of Principles,definition of “one pack year”) Amendment Determination 2022” (No. 94 of 2022), registered on 26 August 2022 and commencing on 19 September 2022. This determination amended only three provisions: the notes to subsections 9(1) and 9(2), and the definition of “one pack year” in the Dictionary. The amendment replaced the previous definition with a more precise one that includes a weight based equivalence of 7,300 grams of smoking tobacco. The notes were updated to reflect the new calculation method.

The legislation history in the compilation shows that original sections 2 and 4 were repealed by operation of the Legislation Act 2003 (sections 48C and 48D) - these were provisions that automatically expire for legislative instruments. This is a routine administrative repeal.

The amendment history is minimal, which suggests that the RMA considered the original definition of pack year to be insufficiently clear. The change likely aimed to reduce disputes over how to calculate equivalent tobacco consumption for pipe and cigar smokers. By providing a weight conversion (1 gram of tobacco equals one cigarette), the amendment standardises measurement and reduces evidentiary ambiguity.

No other amendments have been made as of the compilation date. Future amendments may occur if new medical scientific evidence emerges, for example linking GCA to other exposures such as infections or medications. The SoP is not static; the RMA periodically reviews and reissues Statements of Principles. The compilation notes that uncommenced amendments are not shown, but none are currently scheduled.

The compilation includes an endnote 4 that lists the amendment history: the notes to subsections 9(1) and 9(2) were “rs” (repealed and substituted) by No. 94 of 2022, and the Dictionary definition was similarly substituted. The rest of the instrument remains unchanged.

The source text does not mention any litigation, and as of the compilation date (19 September 2022), there are no reported cases specifically concerning this SoP on giant cell arteritis. However, Statements of Principles under the VEA have been heavily litigated in the Federal Court and High Court, particularly regarding the validity of the reasonableness of the factors and the scope of the RMA’s power. The leading general case law on the reasonable hypothesis standard and SoPs is well established.

The most relevant litigation context is the standard of review. A decision maker’s application of this SoP can be challenged on two main grounds: first, that the SoP itself is invalid (ultra vires s 196B), and second, that the decision maker misapplied the factors or failed to consider whether a factor existed. Challenges to validity are rare because the RMA is given broad discretion, but they have succeeded in the past when the RMA failed to consider relevant evidence or made a factor that was inconsistent with the VEA. For example, in earlier cases, courts struck down SoPs that imposed unrealistic temporal limits or that excluded scientifically plausible factors without justification.

Claims under this SoP could also be litigated over the interpretation of “inability to obtain appropriate clinical management.” This phrase is not defined, and its scope may be contested. For instance, does it cover cases where a veteran was denied treatment due to service related administrative issues? Could it include a veteran who unreasonably refused treatment? The SoP does not answer these questions, leaving room for judicial interpretation.

The pack year definition amendment could also generate disputes. Claimants may contest how pre amendment smoking histories are calculated, given that the definition changed in September 2022. The SoP applies to claims rather than to the date of smoking, so the amending instrument likely applies from its commencement date. However, transitional provisions are not included, so clarity may require litigation.

It is also possible that this SoP could be challenged on the basis that the RMA failed to consider emerging evidence about other causal factors for GCA, such as infections or genetic predisposition. The instrument only includes smoking and inability to obtain appropriate clinical management, which is a narrow set. If new compelling evidence arises, a claimant might argue that the SoP is no longer based on sound medical scientific evidence, but that challenge would need to go to the RMA to amend, not directly to a court.

Overall, while this specific SoP has not been litigated, it sits within a highly litigated field. Any decision applying it may be contested, and practitioners should be aware of the broader judicial framework.

Several features of this SoP can trap unwary claimants and practitioners. The most significant is the pack year threshold and temporal limit. Factor 9(1) requires at least 10 pack years before clinical onset, with onset occurring within 20 years of cessation if smoking has ceased. A claimant who smoked for 9.5 pack years, or who had onset 21 years after cessation, cannot use the smoking factor even if smoking was clearly a cause. The same applies to worsening under factor 9(2). These are bright line rules: there is no discretion to reduce the threshold based on individual susceptibility. Claimants with lighter smoking histories must fall back on factor 9(3) (inability to obtain appropriate clinical management), which may be harder to prove.

The definition of pack year changed in September 2022. The original definition may have been less precise; the amended definition includes a weight based equivalence of 7,300 grams of tobacco per pack year. For claims made before the amendment, the old definition applied. For claims after, the new definition applies. Practitioners need to check the claim date and use the correct definition. The amendment also introduced a conversion of 1 gram of tobacco to one cigarette, which is a simplification that may not reflect actual nicotine or tar content but is easy to apply. However, this conversion may disadvantage users of heavy tobacco products.

The inability to obtain appropriate clinical management factor (9(3)) is a catch all, but it only applies to material contribution or aggravation (section 10(2)). It does not apply to the original acquisition of GCA. That means if a person did not have GCA before or during service and it first arose during service, factor 9(3) cannot be used; only smoking can be used. Furthermore, “inability to obtain appropriate clinical management” is not defined, so decision makers may interpret it narrowly. For example, a veteran who was denied a specific treatment due to a military doctor’s negligence might qualify, but one who simply did not seek care might not. Medical evidence will be crucial.

Section 10(2) limits factors 9(2) and 9(3) to cases where GCA was suffered or contracted before or during service but did not arise out of service. This means that if GCA arose out of service, only the smoking factor (9(1)) is available for the original condition, and factors 9(2) and 9(3) can only be used for worsening. Practitioners must carefully determine the relationship between the condition and service.

can be a trap or a tool. If a factor in section 9 refers to an injury or disease that has its own SoP, the factors of that SoP are imported. But the instrument does not list which injuries or diseases might be relevant. For example, if the inability to obtain appropriate clinical management is due to a service related mental health condition, the SoP for that mental health condition must be satisfied. Claimants may need to meet multiple SoPs to establish one factor.

Compliance with this SoP is not a matter of filing a form; it is about gathering evidence that satisfies the factors and ensuring that evidence is properly connected to relevant service. For claimants and their representatives, the first step is to confirm that the person has relevant service as defined in the Dictionary. If the service is not one of the six categories, the SoP cannot be used, and the claim must be assessed under different rules.

Second, obtain a medical diagnosis of giant cell arteritis that matches the definition in section 7(2). The diagnosis should confirm that the vasculitis involves large and medium sized arteries and principally affects cranial branches of carotid arteries. A diagnosis based on temporal artery biopsy or imaging should specify the affected arteries. The ICD code is not determinative.

Third, gather evidence for at least one factor. For the smoking factor, collect a detailed smoking history: start date, end date, average number of cigarettes per day or equivalent. If the claimant smoked pipes or cigars, convert to grams using the 1 gram = 1 cigarette equivalence from the definition. Calculate pack years: (average cigarettes per day ÷ 20) × years smoked. If the claimant has ceased smoking, verify the date of cessation and ensure clinical onset occurred within 20 years. Onset should be documented by a medical practitioner. If smoking continued, no temporal limit applies, but the onset must still be after the smoking reached 10 pack years.

For the worsening factor, similarly document that worsening occurred after the 10 pack year threshold and within 20 years of cessation. Worsening could be evidenced by increased symptoms, hospitalisation, or new complications.

For the inability to obtain appropriate clinical management factor, gather evidence that appropriate management (such as corticosteroid therapy, tocilizumab, or surgical intervention) was unavailable due to the circumstances of service. This could be shown by service records indicating denial of treatment, limited access to specialists in remote postings, or military medical negligence. The inability must be related to service. Obtain expert medical opinion that the lack of management materially contributed to the progression of GCA.

Fourth, establish the relationship to service. For factor 9(1) (smoking and clinical onset), the smoking itself must be related to service. This is often the hardest part, because smoking is a personal habit. The VEA and case law require that the factor “be related to” service, which means service must have contributed in a material way to the factor. For smoking, this may require evidence that the person started or increased smoking due to service stress or conditions. For factor 9(2) and 9(3), the relationship must be to the material contribution or aggravation, not to the original acquisition.